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5 votes
Need help for number 9

Need help for number 9-example-1
User GoodDeeds
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2 Answers

4 votes
Let x = time (minutes) it takesthenx(1/20 + 1/35) = 1multiplying both sides by common denominator of 700:x(35 + 20) = 700x(55) = 700x = 700/55x = 12.73 minutesorx = 12 minutes and 44 seconds

b - Josh wraps a cloth around the first leak, which cuts the rate of that leak in half. At the same time, it doubles the rate of the second leak. How will this affect the time it takes to fill the bucket?Let x = time (minutes) it takesthenx((1/2)(1/20) + 2(1/35)) = 1x(1/40 + 2/35) = 1multiplying both sides by common denominator of 1400:x(35 + 80) = 1400x(115) = 1400x = 1400/115x = 12.174 minutesorx = 12 minutes and 10 seconds
User Baranco
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8.8k points
4 votes
Oh, I could help you

For the first leak, we lost 20 minutes, that means in 1 minute we can complete 1/20 of this bucket.
For the second, it is the same, we can fill 1/35 of this bucket in 1 minute.
Now, we have two leaks and in 1 minute we can fill 1/20+1/35= 11/140
That means we need 140/11 minute.
Have fun
User Sgtdck
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