Farhan makes desks to earn extra money. in the spring he built 4 times as desks as he did in the summar.If he made 85 desk altogether,how many desks did he built in summer ?

Farhan makes desks to earn extra money. in the spring he built 4 times as desks as he did in the summar.If he made 85 desk altogether,how many desks did he built in summer ?

Explanation

Let 

spring =A 

Summer=B 

A+B=85

A=4B

4B+B=85

5B=85

B=85/5=17

A=4*17=68