JSS 1 Mathematics Flashcards: Finding the Lowest Common Multiple of Whole Numbers

Question 1

What is the least common multiple of 6 and 8?

Accepted Answer

24

Question 2

Find the LCM of 9 and 12.

Accepted Answer

36

Question 3

Find the LCM of 4, 6 and 10.

Accepted Answer

60

Question 4

What is the smallest number divisible by both 15 and 20?

Accepted Answer

60

Question 5

Which number is a common multiple of 7 and 9: 42, 54, 63 or 72?

Accepted Answer

63

Question 6

The LCM of two coprime numbers 5 and 8 is ____.

Accepted Answer

40

Question 7

Using prime factors, what is the LCM of $12=2^2\times3$ and $18=2\times3^2$?

Accepted Answer

36

Question 8

Two bells ring every 6 minutes and 10 minutes. If they ring together now, after how many minutes will they next ring together?

Accepted Answer

30 minutes

Question 9

Three buses leave a stop every 8, 12 and 20 minutes. After how many minutes will all three leave together again?

Accepted Answer

120 minutes

Question 10

If one light flashes every 4 seconds and another every 14 seconds, how many seconds pass before they flash together again?

Accepted Answer

28 seconds

Question 11

What is the LCM of 16 and 24?

Accepted Answer

48

Question 12

Find the LCM of 21 and 28.

Accepted Answer

84

Question 13

Which list contains the first three positive multiples of 6?

Accepted Answer

6, 12, 18

Question 14

What is the least common multiple of a number and itself, such as 13 and 13?

Accepted Answer

13

Question 15

If 6 is a factor of 18, what is the LCM of 6 and 18?

Accepted Answer

18

Question 16

Which is NOT a common multiple of 3 and 4: 12, 24, 36 or 42?

Accepted Answer

42

Question 17

The first two common multiples of 5 and 6 are ____ and ____.

Accepted Answer

30 and 60

Question 18

A number is a multiple of 6, divides 24, and has LCM 24 with 8. What is the number?

Accepted Answer

6

Question 19

What is the LCM of 25 and 30?

Accepted Answer

150

Question 20

A trader visits a market every 12 days and her sister every 18 days. If both visit today, when will they next visit on the same day?

Accepted Answer

in 36 days

Strong work.