3/4 0.75 75% 75% 75% discount.

13/20 0.65 65% 65% 65% discount

2/5 0.4 40% 40% 40%

3/ 10 0.3 30% 30% 30%

15% discount

(1)48÷4×5=60 (kg)

(2) 42 ÷ 7×12 = 72km