Amateur wrote:

Danny and Ian are munching on a jar full of candies. Had Danny eaten alone it would have taken him 5 minutes to finish the candies in the jar. Had Ian eaten alone it would have taken him 10 minutes to finish half the jar. Since both of them are eating simultaneously, how long would it take them to empty the jar?

A. 2.5 minutes

B. 3 minutes

C. 3 minutes and 20 seconds

D. 6 minutes and 40 seconds

E. 4 minutes

Source: HULT

Plug in a good number for the number of candies. E.g. 10 and set up a rate work table:

Danny: Rate 2 / Time 5 / Work 10

Ian: Rate 0.5 / Time 10 / Work 5

Combined Rate: 2.5 / Time 4 / Work 10

Answer E

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