Consider the 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?
 What is the step-by-step reasoning process to arrive at the answer: 21?
The children find 3 + 12 + 8 = 23 insects. After the ladybugs fly away, there are 23 - 2 = 21 insects.