Question

a) Tinh nhanh: 15, 7 + 15, 7 + 15, 7 + 15, 7 * 8 - 15, 7

Answer 1

\(=15,7\times1+15,7\times1+15,7\times1+15,7\times8-15,7\times1\\ =15,7\times\left(1+1+1+8-1\right)\\ 15,7\times10=157\)

Answer 2

`15,7+15,7+15,7+15,7xx8-15,7`

`=15,7xx3+15,7xx8-15,7xx1`

`=15,7xx(3+8-1)`

`=15,7xx10`

`=157`

`@An`