HCF and LCM Year 7

Write 40 as a product of its prime factors.

Write 72 as a product of its prime factors.

Write 98 as a product of its prime factors.

• 2 × 49

• 7 × 14

• 2 × 2 × 7

Write 240 as a product of its prime factors.

Find the highest common factor (HCF) of 60 and 114.

• 6

• 12

• 3

• 10

Find the lowest common multiple (LCM) of 120 and 150.

• 600

• 1800

• 300

• 1200

Find the highest common factor (HCF) of 84 and 120.

• 12

• 6

• 24

• 8

Find the lowest common multiple (LCM) of 70 and 56.

• 280

• 140

• 392

• 112

Two buses, bus A and bus B, both use the same bus stop. Bus A runs every 10 minutes. Bus B runs every 14 minutes. Both buses are at the bus stop at 11 am. What time will both buses next both be at the bus stop?

• 12:20 pm

• 11:30 am

• 12:00 pm

• 12:10 pm

Light A flashes every 8 seconds. Light B flashes every 20 seconds. Both lights flash at the same time. Work out how long it will take for both lights to flash at the same time again.

• 40 seconds

• 28 seconds

• 60 seconds

• 16 seconds