The answer is 5/14
I know because 3/7*5/6=15/42 then you need to find the greatest common factor of 15 and 42.
Now the common factor will be 3 so you have to divide 15 by 3 and you get 5 however what you divide on the top you also divide at the bottom do 42 divided by 3 is 14 now 5 is your numerator and 14 is your denominator so your new fraction is going to be 5/14
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