John decides to buy some birds. He got 50 dollars from each of his 4 grandparents. If each bird costs $20, how many wings did all the birds have?
Let's be accurate as possible. Think before you answer.
20
He got 4 * 50 = $200.

That means he was able to buy 200 / 20 = 10 birds.

Since each bird has 2 wings he got 10 * 2 = 20 wings.

.

Thus, the answer is 20