Answer: 9/20 voted
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Step-by-step explanation:
Let's say there are 100 students total. You can start with any number you want, but I'm picking a large round number to work with.
3/5 of the total voted, so (3/5)*100 = 0.6*100 = 60 people voted
Of the 60 who voted, 3/4 of those went to the winning candidate.
3/4 of 60 = (3/4)*60 = 0.75*60 = 45
We have 45 people who voted for the winning candidate out of 100 total students, so,
45/100 = (9*5)/(20*5) = 9/20
Meaning that 9/20 of the student body voted for the winning candidate.
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You could also multiply the two given fractions to get the same answer
(3/5)*(3/4) = (3*3)/(5*4) = 9/20
When multiplying, you multiply the numerators together and the denominators together. Reduce the fraction if possible.