Betty and Colin were making some cards for an event. Each day, Betty made 12 cards and Colin made 18 cards. Betty started making her cards 20 days earlier. How many days would Colin take to make the same number of cards as Betty?
12 x 20 = 240 (Betty’s head start)
18 – 12 = 6 (more cards Colin made than Betty each day)
240/6 = 40
Ans : 40 days.