Question

Divide 25 into two parts such that 7 times the first part added to 5 times the second part makes 139.

Answer 1

This word problem related to linear

equations in one variable.

Given sum of two parts = 25

Let first part = x

second part should be = 25 - x

7 times the first part = 7x

5 times the second part = 5( x - 25 )

Given relation between to parts is

7 times the first part added to 5 times

the second part = 139

Now write the word problem into 

Linear equation

7x + 5( 25 - x ) = 139

7x + 125 - 5x = 139

2x = 139 - 125

2x = 14

x = 14/ 2