A pen costs $9 more than $2 which is $9 + $2 = $11. Altogether they cost $11 + $2 = $13.
The answer: 13
Reverse engineering the question: A pen costs $9 more than a pencil. If a pencil costs $2, find the total cost of both items.

The total amount of money that Vivienne gets from selling her phones is 40 * 400 = 16000. Since Aliyah has 10 more phones than Vivienne, she has 40 + 10 = 50 phones. When she sells her phones, Aliyah receives 50 * $400 = $20000. Together they have $20000 + $16000 = $36000.
The answer: 36000
Reverse engineering the question: Aliyah has 10 more phones than her sister Vivienne. If Vivienne has 40 phones, and the two sisters sell their phones at $400 each, calculate the total amount of money they have together?

First find the total cost of the wasted meat: $5 / pound * 20 pounds = $100. Then find the total cost of the wasted vegetables: $4 / pound * 15 pounds = $60. Then find the total cost of the wasted bread products: $1.50 / pound * 60 pounds = $90. Then find the time - and - a - half rate for the janitors: $10 / hour * 1.5 = $15 / hour. Then multiply that by the number of hours to find the total janitorial cost: $15 / hour * 10 hours = $150. Then add up all the costs to find the total cost of everything: $100 + $60 + $90 + $150 = $400. Then divide the total James owes by his hourly wage to find how many hours he needs to work: $400 / $8 / hour = 50 hours.
The answer: 50
Reverse engineering the question: James started a food fight in his school's cafeteria, and the school administration is making him work off the cost of all the food he wasted at minimum wage ($8). James has to pay for 20 wasted pounds of meat at $5/pound, 15 wasted pounds of fruits and vegetables at $4/pound, 60 wasted pounds of bread products at $1.50/pound, and 10 hours of time-and-a-half pay for the janitorial staff, who normally make $10/hour. How many hours will James have to work to pay for everything?

There are 40 / 2 = 20 women at the event. Hence, there are a total of 40 + 20 = 60 men and women at the event. So, the total number of children at the event is 80 - 60 = 20. After Oleg added 10 children to the guest list, there are a total of 20 + 10 = 30 children.
The answer: 30
Reverse engineering the question:
Oleg is an event organizer. He is organizing an event with 80 guests where 40 of them are men, half the number of men are women, and the rest are children. If he added 10 children to the guest list, how many children will there be at the event?