Dawn and Scott pocket money

Question

Dawn and Scott count the money they each have in their pocket. Dawn has £17.50 and the ratio of Dawn's money to Scott's money is 5:4. Dawn gives £4 to Scott. What is the new ratio between the amounts?

Answer 1

S/4 = 17.5/5 = 3.5, S=4(3.5) = 14. 5:4 = 17.5:14, 5/4 = 17.5/14 = 1.25

D gives 4 to S, then S=18 and D=13.5

the new ratio is 13.5 to 18, 13.5:18, 13.5/18 = 0.75