Question

вычислите. 1/2 +2/5= 1/2- 2/5= 1/4+1/6= 9/10-5/6=

Answer 1

1/2 + 2/5 = 5/10 + 4/10 = 9/10
1/2 - 2/5 = 5/10 - 4/10 = 1/10
1/4 + 1/6 = 3/12 + 2/12 = 5/12
9/10 - 5/6 = 27/30 - 25/30 = 2/30 = 1/15