Question 565319
let s = no. of Steve's cousins
let r = no. of Robin's cousins
:
Write a simple equation for each statement:
:
Steve and Robin have 16 cousins.
 s + r = 16
:
 Steve has 3 times as many as Robin.
s = 3r
:
In the 1st equation we can replace s with 3r
3r + r = 16
4r = 16
r = 16/4
r = 4 cousins for Robin
then we know s = 3r, therefore
s = 3*4
s = 12 cousins for Steve
:
Of course they should add up to 16 which they do