Question

Mik cần gấp [3.(x+2):7].4=120

Answer 1

\(\Leftrightarrow3\left(x+2\right):7=30\)

=>3(x+2)=210

=>x+2=70

hay x=68

Answer 2

\(\left[3\cdot\left(x+2\right)\div7\right]\cdot4=120\)

\(3\cdot\left(x+2\right)\div7=120\div4\)

\(3\cdot\left(x+2\right)\div7=30\)

\(3\left(x+2\right)=30\cdot7\)

\(3\cdot\left(x+2\right)=210\)

x+2=210:3

x+2=70

x=68