Bài 1: Tính :
a) 2/5 + 7/10 = ............................................................................................ b) 6/7 - 5/8 = …………………………………………………………………… c) 3/5 x 15/8 =............................................................................................. d) 1/4 : 3/7 = …………………………………………………………….............
a) = 11/10
b) = 13/56
c) = 9/8
d) = 7/12