By using a suitable method, find the lowest common multiple of 4, 15, 60.

A neon light blinks every 9 seconds whereas another neon light blinks every 12 seconds. If both the lights blink together when the switch is on, after how many seconds will both the neon lights blink together again?

Selva wishes to pack some souvenirs consisting of a key chain and a refrigerator magnet in each pack for her friends. Key chains are sold in 10 pieces per packet whereas refrigerator magnets are sold in 6 pieces per packet. What is the minimum number of key chains Selva has to buy so that the number of refrigerator magnets she buys can be packed exactly with all the key chains?

Find the smallest number that can be divided completely by 8 and 20.

The lowest common multiple of n and 6 is 72. Find the value of n.

Sharif likes exercising. He goes hill-climbing every 12 days and goes swimming every 8 days. If he goes hill-climbing and swimming today, how many days later will he go hill-climbing and swimming on the same day again?

Nurul, Hui Ling and Gopal were each given a piece of ribbon of the same length. They cut their own ribbons into several pieces of the same length. The pieces of ribbon cut by Nurul, Hui Ling and Gopal measured 15 cm, 25 cm and 30 cm long respectively. All the ribbons were cut and there were no remainders left. What was the shortest possible length of the ribbon given to them?

Ai Lin wants to produce a history scrapbook using 24 photographs and 42 newspaper cuttings. She wishes to use all the photographs and newspaper cuttings such that every page of the scrapbook contains the same number of photographs and newspaper cuttings. What is the maximum number of pages she can have for the scrapbook?

The HCF of m and 54 is 6. Find the largest value of m such that the value of m is less than 54.