since you know that 100 pence is equal to one pound, and that one yogurt is equal to 45 pence, convert this this unit to pounds, which would be that 1 pound can buy you 20/9 yogurts. Then, since you want to know how many yogurts you can buy with 5 pounds, you multiply 20/9 by 5 and you get 100/9, or if converted to a mixed fraction, you can buy 11 1/9 yougurts with 5 pounds.
