Problem number 14. The koala ate some leaves from three branches. Each branch had 20 leaves. The koala ate a few leaves from the first branch and then ate as many leaves from the second branch as were left on the first branch. Then it ate two leaves from the third branch. How many leaves in total were left on the three branches? A, 20. B, 22. C, 28. D, 32. E, 38. The koala started with three branches. Each had 20 leaves. From the problem, we already know that it ate two leaves from the third branch. So on the third branch, there were 20 minus two or 18 leaves left. The harder part of this problem is figuring out how many leaves were left on the other two branches. The problem tells us that the koala ate a few leaves from the first branch and then ate as many leaves from the second branch as were left on the first branch. Notice that it does not give us a specific number that it ate from the first branch. So there's probably some kind of a pattern to figure out how many leaves were left. Let's try to find this pattern by trying a few numbers. If the koala ate three leaves from the first branch, then there were 20 minus three or 17 leaves left on this branch. So it would have eaten 17 from the second branch. That would have left the 17 on the first branch and three on the second branch for a total of 20. If it had eaten five leaves for the first branch, there would have been 15 leaves left on the first branch. It would have eaten 15 from the second branch, and it would have left five on the first branch. No matter what number we try, whatever is left on the first branch will be eaten from the second branch, and whatever is eaten from the first branch will be left on the second branch. In other words, it would be like eating one whole branch, or 20. Think of it that way, so that one of the branches is eaten and the other is left. So we have 20 leaves left between the first two branches, and 18 leaves left on the second branch. 20 plus 18 is 38, so the answer is 38.

koala

leaves

branches

math

problem-solving