Revision of Playing with Numbers: Grade 6

54 is a prime number.

• True

• False

1 is the smallest prime number.

• True

• False

The number of multiples of a given number is limited.

• True

• False

The prime factorisation of two digits is given below:

350 = 2 x 5 x 5 x 7

140 = 2 x 2 x 5 x 7

Find the LCM

• 1400

• 70

• 700

• 350

A 4 digit number 51*2 is divisible by 3, where * is the missing digit. Which of these cannot be the values of *?

• 9

• 1

• 4

• 7

Your family decides to take a short trip to the hills. A petrol pump comes after every 5 km on the National Highway. An eatery joint comes every 8 km on the same road. At what distance will there be both an eatery and a petrol pump?

Are 8 and 15 Co-prime?

• Yes

• No

What is the HCF of 8 and 15?

What is the LCM of 8 and 15?

Look at the factor tree given above.

What will come in place of X?