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Jordan can build a birdhouse in 2 hours. If it takes her sister 3 hours to build a birdhouse, how long will it take them to build a birdhouse together?

2 Answers

1 vote

Answer:

if you came on here to find the answer for the A-Beka Algebra 1 quiz 36 for this question the answer is 1 1/5hr. or 1hr.12min.

Explanation:

1. B. Cross multiply

2. D. 1

3. B. proportion

4. A. 4a-2/8a-a^2

5. a=2

6. c=0,6

7. 150ft (or just) 150

8. 1 1/5hr. (OR) 1hr.12min.


User Kathan Shah
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8.0k points
4 votes
To find the total work of two people at different speeds, we need to find a common speed limit to both.

In this case, Jordan can build a birdhouse in 2 hours so her speed is 1/2 birdhouse per hour.

For the sister, it takes 3 hours to build a birdhouse so her speed is 1/3 birdhouse per hour.

To find what they can do in one hour:
(1)/(3) + \frac {1}{2} = (2)/(6) + (3)/(6) = (5)/(6)

To find how long does it take to build a birdhouse:
( (5)/(6))/(1) = (1)/(x)

Set the denominators equal:
((5)/(6)x)/(x) = (1)/(x)

Remove the denominators and solve:
(5x)/(6) = 1

Once again set the denominators equal:
(5x)/(6) = (6)/(6)

Remove the denominators and solve for x:
5x = 6 \\ \\ x = (6)/(5)

6/5 hours is equal to 72 minutes.
User Tom Jelen
by
8.4k points

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