Question

An aquarium at a pet store has 18 Black Neon Tetra fish in it . A customer buys 12 Black neon Tetra Fish at the same time the store clerk adds 7 more Black neon Tetra fish are in the aquarium now ?

Answer 1

18-12+7

 6 + 7

13

Write an equation.

Subtract first- the customer buys 12 black neon tetra fish which means subtraction

addition- the store clerk puts in 7 more black neon tetra fish which means your gonna add 7

Answer 2

18-12. Add 7. Get 13. :)