Reasoning and answer: The black and pink notebook cost a total of $15 + $10 = $25. The green notebooks cost a total of $45 - $25 = $20. Each green notebook cost $20 / 2 = $10.
The answer: 10
What was the question?
Question: Peter bought 4 new notebooks for school. 2 of them are green, one is black and the other one is pink. The total cost was $45. If the black notebook cost $15, and the pink one cost $10, how much did the green notebooks cost each?

Reasoning and answer: The total number of light bulbs in the 20 lamps is 20 * 7 = 140. If 1 / 4 of the 20 lamps have burnt - out light bulbs, there are 1 / 4 * 20 = 5 lamps with burn out light bulbs. Since each of the 5 lamps has 2 burnt - out light bulbs, the number of burn out light bulbs is 2 * 5 = 10. The number of working light bulbs is 140 - 10 = 130.
The answer: 130
What was the question?
Question: Reyna had 20 lamps with seven light bulbs in each lamp. If 1/4 of them have 2 burnt-out light bulbs each, how many light bulbs are working?

Reasoning and answer: There were 600 - 240 = 360 boys at the beginning of the game. So, 360 x 1 / 4 = 90 boys left early. And 240 x 1 / 8 = 30 girls left early. A total of 90 + 30 = 120 people left early. Therefore, 600 - 120 = 480 people remained to see the end of the game.
The answer: 480
What was the question?
Question:
There were 600 people in the stadium when the football game started. Before the game was over, one-fourth of the boys and one-eighth of the girls left early. How many people remained to see the end of the game if there were 240 girls at the beginning of the game?