Hi Tim. If the caterpillar climbs 1/2 inches in 1 hour, and falls back 1/4 inches in the hour it rests, then after 2 hours it only nets 1/4 inches. (1/2 - 1/4 = 1/4). To reach 12 inches at the top of the glass, it will take 8 hours for 1 inch (since it’s 2 hours for 1/4 inch), and then 96 hours for 12 inches. (12 x 8 = 96).
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