Question

a expressão [(3/5)5.(3/5)-1]:(3/5)2

Answer 1

[(3/5). 5 ( 3/5 ) - 1 ] : (3/5) 2 = 
[ 3/5 . 15/5  - 1 ] :  6/5 =
[ 45/25 - 1 ] : 6/5 =
m.m.c = 25
[45/25 - 25/25] : 6/5 = 
[ 20/25] : 6/5 =
20/25 x 5/6 =  100/ 150 = 10/15 = 2/3