Question

怎样简便计算4.5除以4加2.8x25%十2.7x0.25

Answer 1

4.5÷4 + 2.8x25% + 2.7x0.25
=4.5×0.25+2.8x0.25+2.7x0.25
=（4.5+2.8+2.7）x0.25
=10x0.25
=2.5

除以4，就是等于乘以4分之1，就是0.25

追问

为什么4.5乘0.25

追答

除以一个数，等于乘以它的倒数，所以
除以4，就是等于乘以4分之1，就是0.25

Answer 2

4.5÷4+2.8×25%+2.7×0.25
=4.5×0.25+2.8×0.25+2.7×0.25
=(4.5+2.8+2.7)×0.25
=10×0.25
=2.5

追问

为什么？

追答

2.5÷4 除以一个数等于乘以这个数的倒数
=2.5×4分之1
=2.5×0.25

4分之1=0.25和25%=0.25应该没问题吧？