The Matrix

It takes 6 minutes and 12 minutes, respectively, to run two computer programs when they are run one at a time. However, their speeds are reduced by 50% and 40%, respectively, if running in parallel. If a PC starts running the two programs together, how long will it take for them to finish?

A. 17.4 minutes

B. 18 minutes

C. 16 minutes

D. 16.8 minutes

E. 15.5 minutes

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