7.816×1.45+3.14×2.184+1.69×7.816
=7.816×1.45+1.69×7.816+3.14×2.184
=7.816x(1.45+1.69)+3.14x2.184
=7.816x3.14+3.14x2.184
=3.14x(7.816+2.184)
=3.14x10
=31.4
答:答案是31.4.
7.816×1.45+3.14×2.184+1.69×7.816
=7.816×(1.45+1.69)+3.14×2.184
=7.816×3.14+3.14×2.184
=(7.816+2.184)×3.14
=10×3.14
=31.4
7.816×1.45+3.14×2.184+1.69×7.816
=7.816×(1.45+1.69)+3.14×2.184
=7.816×(3.14)+3.14×2.184
3.14x(7.816+2.184)
=3.14x10
=31.4