We have a question: Johnny is an engineer designing a bridge. The roadway deck for the top of the bridge needs 1600 tons of concrete to construct. The two bridge anchors need equal amounts of concrete, but only one has been built so far, using 700 tons of concrete. Johnny had to calculate how many tons of concrete the supporting pillars underneath the bridge would need, and he found that the total amount of concrete in the entire bridge will be 4800 tons. How much concrete did Johnny find he needs for the supporting pillars?
And an answer: 1800
So how you got the answer?
The bridge anchors will take 700 * 2 = 1400 tons of concrete. The roadway deck and bridge anchors need 1600 + 1400 = 3000 tons of concrete. Thus, Johnny found the supporting pillars need 4800 - 3000 = 1800 tons of concrete.

We have a question: Normally Ann can frost a cake in 5 minutes. However, today she has a sprained wrist and it takes her 8 minutes to frost a cake. How much longer would it take her to frost 10 cakes with her sprained wrist?
And an answer: 30
So how you got the answer?
Normally, it would take her 5 * 10 = 50 minutes. With her sprained wrist it will take her 8 * 10 = 80 minutes. 80 - 50 = 30 more minutes.

We have a question: A town is trying to clear litter from its streets. The council pays for adding 14 trash cans to the streets and also pays for adding twice as many trash cans to the back of stores. How many trash cans has the town paid for?
And an answer: 42
So how you got the answer?

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
At the back of stores, the town has paid for 14 trash cans on the streets * 2 = 28 trash cans. The town has therefore added 14 trash cans on the streets + 28 trash cans at the back of stores = 42 trash cans.