[Question]: Will's mom gave him $74 to go shopping. He bought a sweater for $9, a T-shirt for $11 and a pair of shoes for $30. He then returned his shoes for a 90% refund. How much money does Will have left?
[Answer]: Will paid $30 for his shoes but then returned them and got 90% of the money back, so he lost 10% of the money, which means 10 / 100 * $30 = $3 is gone. Will spent $9 + $11 + $3 = $23. Will started with $74 - $23 that he spent = $51 remaining.
So the answer is 51.

[Question]: James builds a 20 story building. The first 10 stories are each 12 feet tall each. The remaining floors are each 3 feet taller. How tall is the building?
[Answer]: The first 10 floors are 10 * 12 = 120 feet. There are a remaining 20 - 10 = 10 stories. They are each 12 + 3 = 15 feet. So those stories are 15 * 10 = 150 feet. So the total height is 120 + 150 = 270 feet.
So the answer is 270.

[Question]: Sami finds 3 spiders in the playground. Hunter sees 12 ants climbing the wall. Ming discovers 8 ladybugs in the sandbox, and watches 2 of them fly away. How many insects are remaining in the playground?
[Answer]:
The children find 3 + 12 + 8 = 23 insects. After the ladybugs fly away, there are 23 - 2 = 21 insects.
So the answer is 21.