Question: Carlo has a music recital next week. He practiced twice as long on Monday as on Tuesday. On Tuesday, he practiced 10 minutes less than on Wednesday. On Wednesday, he practiced 5 minutes more than on Thursday. On Thursday, he practiced for 50 minutes. If he needs to practice for a total of 5 hours that week, how long should Carlo practice on Friday? Think carefully first, then make a decision:
On Wednesday, Carlo practiced for 50 + 5 = 55 minutes. On Tuesday, he practiced for 55 - 10 = 45 minutes. On Monday, he practiced for 45 x 2 = 90 minutes. So, Carlo practiced for a total of 90 + 45 + 55 + 50 = 240 minutes from Monday to Thursday. He needs to practice for a total of 60 x 5 = 300 minutes. Therefore, he should practice for 300 - 240 = 60 minutes on Friday. So the answer is 60.