[Question]: Reina has three times the number of counters and four times the number of marbles as Kevin. If Kevin has 40 counters and 50 marbles, calculate the number of counters and marbles that Reina has?
[Answer]: If Kevin has 40 counters, and Reina has three, the number of counters Kevin has, Reina has 3 * 40 = 120 counters. Reina also has four times the number of marbles that Kevin has, meaning he has 4 * 50 = 200 marbles. In total, Reina has 120 counters + 200 marbles = 320 items.
So the answer is 320.

[Question]: John is very unfit and decides to work up to doing a push-up. He trains 5 days a week for them and starts with wall push-ups. He adds 1 rep a day and once he gets to 15 reps he will start training high elevation push-ups. and then low elevation push-ups, and finally floor push-ups. How many weeks will it take him to get to floor push-ups?
[Answer]: He needs to do 15 * 3 = 45 progressions. That will take 45 / 5 = 9 weeks.
So the answer is 9.

[Question]: Brenda bakes 20 cakes a day. She does this for 9 days and then sells half of the cakes. How many cakes are left with Brenda?
[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.
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After 9 days, Brenda bakes 20 * 9 = 180 cakes. After she sells half of them, the remaining will be 180 / 2 = 90 cakes.
So the answer is 90.