Math Olympiad for Class 6-Problem Solving Approach

The nearest thousands of 39789 will be written as ­­­­­­­­­_______.

a.40000

b.30000

c.29000

d.28000

Round off 444444 to the nearest thousand.

a.444000

b.500000

c.445000

d.400000

Which of the following is the best estimate of 37 x83?

a.35 x 85

b.40 x 80

c.40 x 85

d.30 x 90

Rounding off the given sum to nearest tens. 449+354+4217

a.4700

b.4800

c.5000

d.5020

28 when multiplied by 10.8, we get the approximate result is ­­­­­­_______.

a.302.4

b.302

c.308

d.280

The sum total of 975, 983, 923, 913 and 985 to its nearest hundred will be

a.4500

b.4600

c.4700

d.4800

Estimate 6735 - 396 to nearest tens,

a.6639

b.6340

c.6649

d.6349

What is the approximate value of 275.0003 × 3.005?

a.825

b.830

c.810

d.835

On dividing 93.45 by 0.015, what is the approximate answer?

a.0.6

b.60

c.600

d.6000

Calculate the approximate value of expression.

6885.009 – 419.999 – 94.989

a.6370

b.6830

c.6200

d.6450

What is the approximate value of (8531+ 6307 + 1093) ÷ (501+ 724+ 396)?

a.10

b.7

c.16

d.13

Calculate the value (897 + 635 + 468 – 120 – 721) its nearest hundred.

1100

1200

1300

1000

Calculate the value 1524.79 × 19.92 + 495.26 to its nearest thousand

a.33000

b.34000

c.31000

d.26000

The sum of first 7 multiple of 13 is approximately

360

365

370

375

248.251 12.62 20.52=?

a.400

b.450

c.350

d.600

A water tank had 37625 L of water. Of this 7648 L was used up, approximately what quantity of water (rounded of nearest tens) is left in the container now?

a.30000 L

b.29983 L

c.29980 L

d.29990 L

If 9587 – A = 7429 – 4358, then what is value of A?

a.6516

b.5616

c.6156

d.6616

976 x 237 + 976 x 763 = ?

a.9760

b.7600

c.976000

d.237000

Simplify the following:

3251 + 587 + 369 – A = 3007

a.1250

b.1300

c.1375

d.1200

The product of two numbers is 18432. If one of the number is twice the other, then find the smaller number.

a.48

b.96

c.192

d.82

What number multiplied by 18 gives a product of 846?

a.51

b.48

c.47

d.57

There are 222 red balls in a basket. A boy takes out 6 red balls from it and replaces then by 12 white balls. He continues to do so, till all red balls are replaced by white balls. Then the number of white balls put in the basket is

a.333

b.444

c.345

d.400

1000000 is obtained, when a number is subtracted from the sum of 893645 and 635489, find that number.

106355

364511

51329

529134

The product of three numbers is 7980. In which the product of two numbers is 228, then what is the third number?

25

15

16

35

A shopkeeper charges ₹ 10 for every bottle of coke or ₹ 240 for every carat of 30 bottles. If Vandana wants to buy 185 bottle of coke, what amount she will have to pay?

₹ 1480

₹ 1490

₹ 1600   

₹ 1850

In an examination Karan got 10 marks more than Bhavna. lsha got 5 marks less than Bhavna. If  Trio get a total of 170, then what is the marks obtained by Isha?

65

55

50

45

What is the number which, when divided by 15, gives a quotient 15 and a remainder 5?

80

90

220

230

In a question of division, a student took 8 as a divisor instead of 3, by mistake and finds the answer 15. The correct answer is

15

40

45

120

The average of four numbers is 30. If the sum of first three numbers is 85, the fourth number is

30

35

45

55

If the unit digit in the product (529) x (16 *) x (324) be 2, the smallest digit in place of * will be -

7

2

0

5

In the division sum, dividend is 13462, quotient is 538 and the remainder is 12, then divisor is

30

25

20

35

Which one is greatest?

'The sum of 7985 and largest 4-digit number.

The sum of largest 6-digit number and the least 4-digit number.

8 x 873 + 987

21035 x 2893 - 1893 x 21035

A number is divided by 319. If the remainder and quotient are 217 and 15 respectively, find the number.

7004

4003

5002

4005

Garima opened an account in a bank with ₨ 35000. She deposited ₨ 10000 in her account after 1 month and withdrew ₨ 7000 from her account after 2 months and again deposited ₨ 8000 in her account after 3 months. What is the balance in her account after last transaction?

₨ 43000

₨ 46000

₨ 56000

₨ 36000

A bus runs at a speed of 48 km/h. In how many hours will it travel a distance of 432 km?

8 hrs.

9 hrs.

7 hrs.

6 hrs.

Which of the following gives quotient 25 and remainder 13 when divided by 27?

588

788

598

688

The total number of the prime factor of 24 is

a.8

b.7

c.4

d.9

The number of common factors between 18 and 24 is

a.1

b.8

c.6

d.4

What is the prime factorization of 37800?

a.2 x 2 x 3 x 3 x 5 x 5 x 7 x 7

b.2 x 2 x 2 x 3 x 3 x 5 x 5 x 7

c.8 x 27 x 25 x 7

d.2 x 4 x 25 x 27 x 7

Which of the following is a not a factor of 316?

a.1

b.8

c.79

d.158

The sum of all the prime factors of m is 10. Find the number m.

a.15

b.20

c.28

d.63

Factors of 30 are

a.2, 3, 5

b.1,2,3,5,10

c.1,2,3,10,15

d.1,2,3,5,6,10,15,30

The prime factors of 80 is

a.2 x 2 x 2 x 2 x 5

b.2 x 2 x 2 x 5 x 5

c.2 x 2 x 2 x 5

d.2 x 2 x 5 x 5

The number of multiples of 3 which are less than 25 is

a.6

b.7

c.8

d.9

The sum of the factors of 81 is

a.141

b.121

c.110

d.114

Among the following numbers, which are common multiples of 18 and 54

a.32 and 48

b.54 and 72

c.48 and 72

d.54 and 108

What are the numbers of multiples of 5, which are less than 45?

9

8

7

10

Common multiple for the numbers 4, 8 and 10, within the first 10 multiples is

40

20

50

48

Which of the following is a prime factor?

48 = 2 x 2 x 2 x 6

63 = 3 x 3 x 7

81 = 3 x 3 x 9

54 = 2 x 3 x 9

The sum of first five even multiples of 2 is

28

32

40

30

The number x, x - 2 and x - 6 are all prime numbers, so find the value of x.

15

17

19

21

Find the LCM of 12, 18 and 24.

72

48

60

84

Find the smallest number divided by 42, 98 and 70.

1470

1740

1070

980

LCM of 42, 70, 98 and 126 is

126

2205

4410

8820

LCM of 2 x 3 x 5 and 3 x 5 x 7 is equal to

3

3 x 5

2 x 3 x 5 x 7

2 x 3 x 5 x 3 x 5 x 7

What will be the HCF of 48, 144 and 576?

576

144

48

1

HCF of 5 x 7 x 9 x 11 x 13 and 9 x 11 x 13 x 17 is equal to

13

33

9 x 11 x 13

5 x 7 x 9 x 11 x 13 x 17

Three bells ring at intervals of 12, 15 and 18 min, respectively. They started ringing simultaneously at 9: 00 am. What will be the next time when they all ring simultaneously?

10:00 am

11:00 am

12:00 pm

1:00 pm

Find the HCF of 45, 75 and 165.

15

45

75

2475

The HCF and LCM of two numbers are 4 and 48, respectively. If one of these numbers is 12, then the other number is

16

12

8

4

HCF of two numbers is 20 and their LCM is 120. If one number is 60 find the other.

40

50

30

60

Greatest number, which is to be divided by 280 and 1245 leaves the remainder 4 and 3 respectively, is

138

148

145

178

The difference between the LCM and HCF of the numbers 30, 36 and 90 is

366

354

186

174

Six bells begin tolling together and toll at interval of 2s, 4s, 6s, 8s, 10s, 12s, respectively. The time after which they will toll together is

2 min

103 s

150 s

1 min

Find the least number which when divided by 9, 12, 16 or 20 leaves 3 as remainder each case

723

1725

727

1729

Two numbers are in the ratio 3: 4 and the product of their LCM and, HCF is 10800.Find the sum of the numbers

190

70

210

200

The LCM and the HCF of the numbers 28 and 42 are in the ratio

6:1

2:3

3:2

7:2

The greatest number which will divide 2112 and 2792 leaving 4 as the remainder in each case is

68

58

78

188

The least number such that, when it divided by 15, 25, 35 And 45, it leaves remainder 7, 17, 27, and 37 respectively, is

1575

1557

1576

1567

The product of two numbers is 23625 and LCM is 315. The HCF of the number is

315

23625

75

15

The HCF of 35, 39 and 314 is

314

39

35

328

Four electronic devices make a beep after every 45 minutes, 1 hour, 1 hour 15 minutes and 1 hour 30 minutes respectively. All the devices beeped together at 12 noon. At what time will they beep together again?

3 a.m.

4 a.m.

5 a.m.

12 mid night

Find the LCM of (2²× 3² × 5 × 7), (2³× 3 × 5³ × 74) and (2² × 3² × 7² ×11²).

2³ × 3² × 5³×74 × 11²  

2³ × 3² × 5³ ×74 × 11

2³ × 3² × 5³ ×7³× 11²  

2³ × 3² × 5³ ×7³ × 11³

The HCF and LCM of two numbers ? and ? are respectively 11 and 7632. If ? + ? = 583, then   1/?+1/?  = ?

1/126 

1/144   

1/134 

1/121 

The greatest number of 5-digits, which is divisible by 16, 25, 40, 80 is _

99999

99600

99000

99500

What is the least number which when reduced by 5 is divisible by each one of 21, 28, 36, 45?

425

1259

1260

1265

If the number 517*324 is completely divisible by 3, then the smallest whole number in place of * will be

0

1

2

4

If the number 481*673 is completely divisible by 9, then the smallest whole number in place of * will be

2

5

6

7

If the number 97215*6 is completely divisible by 11, then the smallest whole number in place of * will be

3

2

1

5

If the number 91876*2 is completely divisible by 8, then the smallest whole number in place of * will be

1

2

3

4

Which one of the following numbers is completely divisible by 45?

181560

331145

202860

20335500

Which one of the following numbers is completely divisible by 99?

3572404

135792

913464

114345

What smallest number should be added to 4456 so that the sum is completely divisible by 6?

4

3

2

1

Which natural number is nearest to 9217, which is completely divisible by 88?

9152

9240

9064

9184

Find the greatest 5-digit number divisible by 14

99989

99888

99988

10000

Five digits’ smallest number, which is completely divisible by 75 is

10025

10050

10075

9975

Sum of two integers is −45. If one of the integers is 25 then what is the other integer?

a.−45

b.−25

c.−70

d.None of these

Simplify 200 − 5 [ 25 − {15 + 2 − 12}] = _____

a.200

b.100

c.150

d.175

Simplify (8×21×24 )/(48×7×15)

a.3/5

b.4/5

c.1/7

d.1/2

Find the value of 1 2/3 + 4 6/7.

a.6 12/21

b.6 11/21

c.6 13/14

d.6 11/23

When (1/2-1/4+1/5-1/6) is divided by(2/5-5/9+3/5-7/18), the result is:

a.2 1/18

b.3 1/( 6)

c.3 3/10

d.5 1/10

1 +1/2+1/4+1/7 + 1/14+1/28 is equal to:

a.2

b.2 1/2

c.3

d.31/2

13/4 + 5 1/3 +3 1/2 is equal to:

a.9 2/5

b.9 29/60

c.10 7/12

d.10 27/12

1/5th part of a drum is filled with milk. What is the capacity of the drum if it requires 28 L more to fall the drum completely?

a.30 L

b.32 L

c.35 L

d.140 L

5/6 of an hour is equal to

a.1/(2 )h

b.40 min

c.50 min

d.55 min

By how much is three-fifth of 350 greater than four-seventh of 210?

90

110

120

210

Two-fifth of one-fourth of three-seventh of a number is 15. What is half of that number?

94

175

188

196

1/3 rd part of a certain amount was given to Sita and rest to Gita. If Gita got ₹ 524, what did Sita get?

₹ 262

₹ 412

₹ 200

₹ 400

Which fraction should be added to the sum of 5 3/4, 4 4/5, 7 3/8, to make the result a whole number? 

1/40

2/40

3/40

4/40

A man spends 2/5 of his salary on house rent, 3/10 of his salary on food and 1/8 of his salary on conveyance. If he has ₹1400 left with him, find his expenditure on food.

₹ 2000

₹ 2200

₹ 2400

₹ 2500

The value of 5 -(2 1/2 - 3/4)  + (3 1/2-1 1/4) is

4  1/2

5  1/2

5  1/4

3 1/2

If 4/5 of an item be worth ₹ 1680, find the value of half of the item?

₹ 1080

₹ 1200

₹ 1000

₹ 1050

Which fraction is the greatest fraction? 1/6, 3/6, 4/6, 5/6

1/6

3/6

4/6

5/6

Which is the smallest fraction?

2/5

7/5

6/5

7/8

The correct arrangement of the fractional numbers 17/25, 17/13 , 17/19  and 17/27 in ascending order is

17/19,  17/13,  17/27,  17/25

17/27,  17/25,  17/19,  17/13

17/27,  17/19,  17/13,  17/25

17/13,  17/25,  17/19,  17/27

Which of the following fraction is arranged in descending order?

23/13,  23/11, 23/7, 23/3       

23/3, 23/7, 23/11, 23/13       

23/13, 23/11, 23/3, 23/7     

23/3, 23/7, 23/13, 23/11 

Simplify the following in the simplest form: (7 1/2−3 2/3)×12/69+5/18÷(2/3−1/6)

5/9

11/9   

2/9

1/9   

1.11 + 11.11 + 111.111 is equal to

a.123.331

b.133.331

c.122.331

d.123.311

The product of 1.2 x 0.6 x 3.12 x 0.03 is equal to

a.0.067392

b.0.063568

c.0.4812

d.0.00392

When 61/4 is multiplied by 0.25, then 0.75 is added in result, then 0.3125 is subtracted from result, we get______________.

a.2.15

b.4.25

c.0

d.1.75

Which of the following is equal to 12?

a.0.15 x 0.800

b.0.20 x 0.600

c.0.15 x 800

d.0.20 x 60

Difference between the place value of 7s in 187.978 is_______.

a.0.707

b.7.7

c.7.07

d.6.93

Ram bought a book for ₹178.50, some medicines for ₹248.25 and gave a ₹500 note to the shopkeeper. The remaining amount is

a.₹126.50

b.₹70.50

c.₹75.50

d.₹73.25

How many digits will be there to the right of the decimal point in the product of 95.75 and .02554?

a.5

b.6

c.7

d.3

Which one of the following has the same value as

4+2/25 + 1/5

a.4.21

b.4.28

c.42.1

d.421.0

The decimal equivalent to 3/4+ 4/5+ 8/25

a.1.870

b.18.70

c.187

d.1870

What is the decimal equivalent of 1 5/8 ?

a.1.58

b.1.62

c.1.622

d.1.625

Find the area of the rectangle whose length is 15 cm and the width is 4 cm?

90 cm²

60 cm²

70 cm²

30 cm²

If each side of square will be doubled, then its perimeter will be

2 times

3 times

4 times

8 times

The perimeter of a square park is 72 m, then the area of the square is

144 sq m

2376 sq m

1296 sq m

324 sq m

Find the breadth of a room whose floor area is 363 sq m and length is 33 m.

33 m

24 m

11 m

15 m

The breadth of a rectangle is 3/5 of the length. If the length of the rectangle is 25 m, then find the perimeter of the rectangle.

100 m

80 m

75 m

150 m