Quiz Discussion

Four bells ring at intervals of 6, 8, 12 and 18 seconds respectively since 12 o’clock. How many times will they ring simultaneously within 6 minutes of the time? (excluding the one at the start)

• 1]

  3

• 2]

  4

• 3]

  5

• 4]

  6

Product of two coprime numbers is 117, then their LCM is

• 1]

  9

• 2]

  13

• 3]

  39

• 4]

  117

The product of two numbers is 2028 and their HCF is 13. The number of such pairs is :

• 1]

  1

• 2]

  2

• 3]

  3

• 4]

  4

Find the LCM of 2/3, 3/5, 4/7 and 9/13.

• 1]

  36

• 2]

  1/36

• 3]

  1/1365

• 4]

  12/455

The LCM of two numbers is 495 and their HCF is 5. If the sum of the numbers is 100 then their difference is:

• 1]

  10

• 2]

  46

• 3]

  70

• 4]

  90

How many numbers are there between 2000 and 4000 which are divisible by 2,3,4 and 5?

• 1]

  32

• 2]

  33

• 3]

  34

• 4]

  35

The LCM and HCF of two numbers are 84 and 21, respectively. If the ratio of the two numbers is 1 : 4, then the larger of the two numbers is

• 1]

  12

• 2]

  48

• 3]

  84

• 4]

  108

Which of the following is a pair of co-primes?

• 1]

  (14,35)

• 2]

  (18,25)

• 3]

  (31,93)

• 4]

  (32,62)

 What is the greatest number which when subtracted from 3000, is exactly divisible by 7, 11 and 13 ?

• 1]

  1999

• 2]

  3000

• 3]

  10001

• 4]

  3050

The greatest number which on dividing 1657 and 2037 leaves remainders 6 and 5 respectively is

• 1]

  271

• 2]

  172

• 3]

  721

• 4]

  127