Cars are made in a factory at a rate of 39 cars every 3 hours. at this rate, how many cars can be made in the factory in 7 hours?
a: 43
b: 91
c: 124

No of cars made in 3 hours = 39
No of cars made in 7 hours = (39/3)*7
                                            = 13 * 7
                                            = 91 cars

So answer B

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