Step-by-step explanation:
a) 2/5 × 5/7 = 10/35 ➡ 2/7 (if needed to simplify)
b) 16/25 × 2/4 = 32/100 ➡ 8/25
c) 15/6 ÷ 3/15 ➡ 15/6 × 15/3 = 25/2
d) 4/11 × 12/9 = 16/33
e) 3/5 × 7/12 = 7/20
f) 9/27 × 2/6 ➡ 9/27 × 6/2 = 3
