GCF and LCM

Front

The GCF of 25 and 30

Back

5

Front

GCF of 1283 and 9299

Back

1

Front

Lane strikes her drum every 9 seconds and Rory plucks her guitar every 15 seconds. After how many seconds will they next strike and pluck together?

Back

45 Seconds

Front

David has a length of ribbon which is 180cm long. Kylie’s length of ribbon is 225cm long. They want to cut the longest lengths of ribbon they can from their lengths without wasting any, and in such a way that every piece of ribbon they cut is equal in length. How long will the lengths be?

Back

45 cm

Front

Express 960 as the product of prime factors. Use your result to show that 15 is the largest odd factor of 960.

Back

2^6 × 3 × 5; 3 and 5 are the only odd factors so 3×5 is the largest odd factor.

Front

The children at Freeferal Primary School are going on a school trip to Blackpool and every pupil who wants to attend must pay to do so. Mr N Rooly collects £255 from his pupils. Mrs K Ottick collects £136 from her pupils. What is the highest cost per pupil?

Back

£17

Front

HCF: 32, LCM: 640. What could the two numbers be? Options: 32 and 128 or 160 and 640, 160 and 32 or 128 and 640, 640 and 128 or 32 and 160, 160 and 128 or 32 and 640.

Back

160 and 128 or 32 and 640

Front

Cain washes his bedding every 4 weeks. Chas washes her bedding every 5 days. If they both wash their bedding on April 1st, what is the next date they will both wash their bedding?

Back

August 18th (LCM of 28 and 5 is 140 days)

Front

Express 5625 as the product of prime factors to show it is a square number.

Back

Front

Use prime factorisation to show that 27 000 is a cube number and find its cube root.

Back

27 000 = 2^3 × 3^3 × 5^3 = (2 × 3 × 5)^3 = 30^3