计算(1)(347-347×25)×0.7×16(2)7.816×1.45+1.69×7.816+3.14×2.184(3)215×4.69+3.21×1025+7.9÷1213(4)(1+711)+(2+711×2)+(3+711×3)+…+(11+711×11).-数学
题文
计算 (1)(3
(2)7.816×1.45+1.69×7.816+3.14×2.184 (3)
(4)(1+
|
答案
(1)(3
=3
=
=0.25; (2)7.816×1.45+1.69×7.816+3.14×2.184, =7.816×(1.45+1.69)+3.14×2.184, =7.816×3.14+3.14×2.184, =3.14×(7.186+2.184), =3.14×9.37, =3.14×(10-0.63), =31.4-1.9782, =29.4218; (3)
=
=
|