解方程:二分之x-1=二分之十二-x,第二个问题是2.2×0.25×8×【12.7-(7.25+4.5)】÷3.8

问题描述:

解方程:二分之x-1=二分之十二-x,第二个问题是2.2×0.25×8×【12.7-(7.25+4.5)】÷3.8

二分之(x-1)=二分之(十二-x) x-1=12-x 2x=13 x=6.5 2.2×0.25×8×【12.7-(7.25+4.5)】÷3.8 =2.2×2×(12.7-11.75)÷3.8 =4.4×0.95÷3.8 =4.18÷3.8 =1.1