作业帮7.5×46.7+39.9×2.5等于多少（简便运算）
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/15 18:53:48
7.5×46.7+39.9×2.5等于多少（简便运算）
7.5×46.7+39.9×2.5等于多少（简便运算）
7.5×46.7+39.9×2.5等于多少（简便运算）
7.5*46.7+39.9*2.5
=7.5*46.7+(46.7-6.8)*2.5
=46.7*(7.5+2.5)-6.8*(5/2)
=467-17
=450
975.375九百七十五点三七五
7.5×46.7+39.9×2.5=2.5×[(50-3.3)×3+39.9]=2.5×(150-9.9+39.9)=2.5×180=2.5×4×45=450
原式=7.5*（46.7+13.3）
=7.5*60
=450
7.5×46.7+39.9×2.5
=2.5×3×46.7+2.5×39.9
=2.5×（140.1+39.9）
=2.5×180
=450
原式=2.5*3*46.7+39.9*2.5=2.5*（3*46.7+39.9）=2.5*180=450
原式=2.5×3×46.7+39.9×2.5
=2.5×140.1+39.9×2.5
=2.5×（140.1+39.9）
=2.5×180
=450
=7.5x(39.9+6.8)+39.9x2.5=10x39.9+7.5x6.8=399+6.8/4x30=399+51=450
7.5*46.7+3.9*2.5
=7.5*46.7+7.5*(39.9/3)
=7.5*(46.7+13.3)
=7.5*60
=450
7.5*46.7+39.9*2.5
=7.5*46.7+7.5*(39.9/3)
=7.5*(46.7+13.3)
=7.5*60
= 450
（10-2.5）*46.7+39.9*2.5=467-（46.7-39.9）*2.5=467-6.8*10/4=467-17=450
>> 7.5*46.7+39.9*2.5
ans =
450
结果是450
希望我的回答会对你有帮助！
Sn=a1*n+{n(n-1)/2}*d=n+n(n-1)=n^2