Question

Observând ca numitorul uneia dintre fractii este divizor al numitorului celeilalte reactii,efectuati:
a) 4/15+2/3
b) 16/93+6/31
c) 7/32-1/16
d) 23/42-5/14

Dau coroana

Answer 1

a)   4/15+2/3 = 4/15 + (5×2)/(5×3) = 4/15 + 10/15 = 14/15

b)   16/93+6/31= 16/93 + (3×6)/(3×31)= 16/93 + 18/93 = 34/93 

c)   7/32 - 1/16 = 7/32 - (2×1)/(2×16)= 7/32 - 2/32 = 5/32

d)   23/42 - 5/14 = 23/42 - (3×5)/(3×14) = 23/42 - 15/42 = 8/42 = 4/21