A hobby shop has 4 times as many model airplanes as model helicopters. The total number of models is 35. How many model airplanes does the hobby shop have?

Question

A hobby shop has 4 times as many model airplanes as model helicopters. The total number of models is 35.  How many model airplanes does the hobby shop have?

anonymous · Answer

Let y be number of airplanes models
x be the helicopters models
y = 4x because number of airplanes models are 4times more than that of helicoptors

SImilarly total number of modes are 35 , so y + x = 35.

two equation, 
y = 4x
x + y = 35

Two unknown find it.

anonymous · Answer

?

anonymous · Answer

in second equation put 4x instead of y, 
|dw:1455253380585:dw|
Similarly find y.