Grade 6 Maths Factors and Multiples Quiz (Part A)

Which of the following numbers is divisible by 3?

• 24357806

• 35769812

• 83479560

• 3336433

Answer explanation

The number 83479560 is divisible by 3 because the sum of its digits (8+3+4+7+9+5+6+0) equals 42, which is divisible by 3.

Which of the following numbers is divisible by 9 ?

• 8576901

• 96345210

• 67594310

• none of these

Answer explanation

The number 8576901 is divisible by 9 because the sum of its digits (8+5+7+6+9+0+1) equals 36, which is divisible by 9. Therefore, the correct choice is 8576901.

Which of the following numbers is divisible by 4 ?

• 78653234

• 98765042

• 24689602

• 87941032

Answer explanation

The number 87941032 is divisible by 4 because the last two digits form a number that is divisible by 4, which is a rule for divisibility by 4.

If a and b are co-primes , then their LCM is ________.

• 1

• ab

• none of these

Answer explanation

If a and b are co-primes, their LCM is ab. This is because when two numbers are co-prime, their LCM is the product of the two numbers.

The HCF of two co-primes is

• the smaller number

• the larger number

• 1

• none of these

Answer explanation

The HCF of two co-primes is always 1 because co-prime numbers have no common factors other than 1. Therefore, the correct answer is 1.

The smallest number which when diminished by 3 is divisible by 14, 28, 36 and 45 is

• 1257

• 1260

• 
  1263

• none of these

Answer explanation

The smallest number that when diminished by 3 is divisible by 14, 28, 36, and 45 is found by taking the LCM of these numbers and adding 3. LCM(14, 28, 36, 45) = 1260. Therefore, the smallest number is 1260 + 3 = 1263.

The LCM of 12, 15, 20, 27 is ________.

• 270

• 360

• 480

• 540

Answer explanation

The correct choice is 540 because it is the least common multiple (LCM) of 12, 15, 20, and 27.

The LCM of 24, 36, 40 is ________.

• 4

• 90

• 360

• 720

Answer explanation

The correct answer is 360 because it is the least common multiple of 24, 36, and 40.

The greatest number which divides 134 and 167 leaving 2 as remainder in each case is

• 14

• 17

• 19

• 33

Answer explanation

To find the greatest number that divides 134 and 167 leaving a remainder of 2, we need to find the common factors of (134-2) and (167-2), which are 132 and 165. The greatest common factor of 132 and 165 is 33, making it the correct choice.