Question

Tính biểu thức sau:

a) 1978*1979+1980*21+1958 / 1980*1979-1978*1979 + 100

b)1:17,5*24+13,4*24-7,9*24 / 1+4+7+...+55+58-39*11

Answer 1

a)\(\frac{1978x1979+1980x21+1958}{1980x1979-1978x1979+100}\)

\(=\frac{1978x1979+\left(1+1979\right)x21+1958}{\left(1980-1978\right)x1979+100}\)

\(=\frac{1978x1979+1979x21+21+1958}{2x1979+2x50}\)

\(=\frac{1979x\left(1978+21\right)+\left(21+1958\right)}{2x\left(1979+50\right)}\)

\(=\frac{1979x1999+1979x1}{2x2029}\)

\(=\frac{1979x2000}{2x2029}\)

\(=\frac{1979000}{2029}\)

 

Answer 2

thanh you