Question

se a = 3/4
e b= 2/5
então (a+b) e (a.b) são respectivamente iguais a:

A)23/20 e 5/9. C)23/20 e 3/10

B)5/9 e 3/10. D)23/20 e 15/8

Answer 1

a = 3/4

b =  2/5

a + b = 3/4 + 2/5 =  ( 15 + 8 ) /20   = 23/20 **** resposta

a * b =  3/4 * 2/5 = 6/20 =  3/10 resposta  ***

( c )