(17/20+14.15)*[1-(-1/2)÷7/8]-(-2)^3*(-1/2)^2

问题描述:

(17/20+14.15)*[1-(-1/2)÷7/8]-(-2)^3*(-1/2)^2

(17/20+14.15)*[1-(-1/2)÷7/8]-(-2)^3*(-1/2)^2
=15*[1+4/7]+8*1/4
=15*11/7+2
=23又4/7+3
=25又4/7