Answer the following question.
There are 50 children at the party. Three-fifths of them are boys. How many of the children are girls?
Step-by-step reasoning process: 50 x 3 / 5 = 30 children are boys. So, there are 50 - 30 = 20 children that are girls.
The answer is 20.

Answer the following question.
Jason spent 1/4 of his money and an additional $10 on some books. He then spent 2/5 of the remaining money and an additional $8 on some DVDs. If he was left with $130, how much money did he have at first?
Step-by-step reasoning process: Let X be the money Jason had at first. Jason spent 1 / 4 * X + 10 on books. Jason spent 2 / 5 * [X - (1 / 4 * X + 10)] + 8 on some DVDs. Jason has X - (1 / 4 * X + 10) - {2 / 5 * [X - (1 / 4 * X + 10)] + 8} = $130 left. X - 1 / 4 * X - 10 - 2 / 5 * X + 1 / 10 * X + 4 - 8 = $130. 9 / 20 * X - 14 = $130. X = $320.
The answer is 320.

Answer the following question.
Jessie's community built a new hedge. Each section of the hedge used 30 pieces of concrete blocks that cost $2 per piece. The hedge has eight sections. How much did they spend on the concrete blocks?
Step-by-step reasoning process: They used 30 x 8 = 240 concrete blocks for the eight sections. So, they spent 240 x $2 = $480 on the concrete blocks.
The answer is 480.

Answer the following question.
John pays for half the cost of raising a child. It cost $10,000 a year for the first 8 years and then twice that much per year until the child is 18. University tuition then costs $250,000. How much did it cost?
Step-by-step reasoning process: The first 8 years cost 8 * 10,000 = $80,000. The next 18 - 8 = 10 years. They cost 10000 * 2 = $20,000 per year. So they cost 20,000 * 10 = $200,000. So the cost was 200,000 + 80,000 = $280,000. Adding in the cost of tuition brings the cost to 250,000 + 280,000 = $530,000. Since John pays for half the cost of raising the child, he pays $530000 / 2 = 265000.
The answer is 265000.