Iskander, Anthony and Sean have a total of 555 stamps. Anthony has 13 more stamps than Iskander. Sean has twice the total number of stamps as Anthony and Iskander have. How many stamps does Anthony have?
Let's write it out using algebra. Iskander is I, Anthony is A, and Sean is S.
Let's solve for I first.
Lets bring A= I+13 into S=(A+I)2
Lets bring S=4I+26 and A= I+13 into I+A+S=555
But, we want A. So we bring I=86 into A= I+13.
Hope this helps.