A student weighs her hamsters two at a time. Sandy and white ears weigh 209 g together. White ears and sport weigh 223 g together. Sandy and sport weigh 216 together. How much does each hamster weigh?

Answer 1

Let Sa = weight of sandy
Let W = weight of white ears
Let Sp = weight of sport

Sa + W = 209
W + Sp = 223
Sa + Sp = 216
Three equations and three unknowns. Solve.

Answer 2

s+w = 209
w + p = 223 , where p is sport, (already used s)
s + p = 216

s+w = 209 ----> w = 209 - s
w + p = 223 --- w = 223 - p
then 209 - s = 223 - p
p - s = 14
add this to the third equation and it all comes apart nicely