Question

y nhan 15 + y nhan 13 = 560 nhan 45

Answer 1

y x 15 + y x 13 = 560 x 45 

y x ( 15 + 13 ) = 25200

y x 28 = 25200

y = 25200: 28

y = 900 

Answer 2

\(y\times15+y\times13=560\times45\)

\(y\times\left(15+13\right)=25200\)

\(y\times28=25200\)

\(y=25200:28\)

\(y=900\)