15 machines prepare 360 sweaters in 6 days. 3 machines get out of order. How many sweaters can be prepared in 10 days by the remaining machines? 

Solution: 
Given: 
Total Machine = 15
Machine get out order = 3
Remaining machine = 15 -3 = 12

As the machine decrease, the sweaters production will decrease. so, It is a direct proportion. 
As the number of days increase, the sweaters production will also increases. It is also a direct proportion. 
Let the numbers of sweaters be ï½˜ then,


Here the equation will be 

`\frac{ｘ}{360}`  = `\frac{12}{15}` ï½˜ `\frac{10}{6}` 

Or

ｘ = `\frac{12}{15}` ï½˜ `\frac{10}{6}`     ï½˜ 360 Sweaters

by simplifying we get

ｘ =  480 Sweaters.

Thus, 480 Sweaters will be prepared.