Solving equations

Question

Coach Gibbs is ordering her dog bones if she buys a Bones from store a it will cost $1 per pound plus $10 shipping if she buys her dog bones from store be it will cost $0.50 per bone and $20 shipping how many bones will she buy if it cost the same amount from either store

Answer 1

Store A: cost=10+b dollars, where b is the number of bones.

Store B: cost=20+0.5b

The two costs are equal when 10+b=20+0.5b.

0.5b=20-10=10 so b=20. The cost for each store is 20+10=$30 for 20 bones.