Solve this:

Q.  From two packets of crayons, five crayons were removed and now there are 15 crayons in all. How many crayons were there in each packet? (The two have the same number of crayons)
 

Dear Student,
Let the original number of crayons were x.
Now, x - 5 =15   (As 5 crayons were removed and after that number of crayons were 15)
=> x =5 +15 = 20
Now 20 crayons are in 2 box . 
So no. of crayons in each box will be, 20 divided by 2 => 20/2 = 10
No. of crayons in each box will be 10. 

Regards