Question: There are 5 houses on a street, and each of the first four houses has 3 gnomes in the garden. If there are a total of 20 gnomes on the street, how many gnomes does the fifth house have?
Answer with step-by-step thinking: In the first four houses, there are a total of 4 houses * 3 gnomes = 12 gnomes. Therefore, the fifth house had 20 total gnomes 12 gnomes = 8 gnomes.
So the answer is 8.

Question: Mike can type 65 words per minute. Due to a minor accident, Mike cannot use his right hand for a while so that his typing speed is now 20 words less per minute. If he is supposed to type a document with 810 words, how many minutes will it take him to finish typing the document?
Answer with step-by-step thinking: After the accident, Mike can only type 65 words / minute - 20 words / minute = 45 words / minute. So, he will be able to finish typing the document in 810 words / 45 words / minute = 18 minutes.
So the answer is 18.

Question: Elvis is releasing a new album with 10 songs, but he doesn't want to waste too much time on writing. He spends 5 hours in the studio, where he writes, records, and edits his songs. Each song takes 12 minutes to record, then it takes 30 minutes to edit all of his songs. How many minutes did it take Elvis to write each song, if each song took the same amount of time to write?
Answer with step-by-step thinking:
5 hours in the studio is the same as 5 * 60 = 300 minutes. To record all of his songs, Elvis takes 12 * 10 = 120 minutes. After editing and recording 300 120 30 = 150 minutes are left to write all of his songs. Songwriting therefore took 150 / 10 = 15 minutes per song.
So the answer is 15.