Applying rational equations 1 | Polynomial and rational functions | Algebra II | Khan Academy

TL;DR

Ian can rake and bag a lawn in 5 hours, Kyandre can do it in 3 hours. Working together, it will take them 1 hour and 52.5 minutes.

Transcript

Ian can rake a lawn and bag the leaves in 5 hours. Kyandre can rake the same lawn and bag the leaves in 3 hours. Working together, how long would it take them to rake the lawn and bag the leaves? So let's think about it a little bit. It says Ian can rake a lawn and bag of the leaves in 5 hours. So for Ian, I for Ian. For 1 lawn, he can do 1 lawn in... Read More

Key Insights

• ☠️ Ian's rate is 1/5 lawn per hour, Kyandre's rate is 1/3 lawn per hour.
• ☠️ The combined rate is the sum of Ian and Kyandre's rates, which is 8/15 lawns per hour.
• ☠️ To find the time it takes to complete a task, the reciprocal of the rate gives the answer.

Questions & Answers

Q: How long does it take Ian to rake and bag a lawn?

Ian takes 5 hours to rake and bag a lawn, or 1/5 of a lawn per hour.

Q: How long does it take Kyandre to rake and bag a lawn?

Kyandre takes 3 hours to rake and bag a lawn, or 1/3 of a lawn per hour.

Q: What is the combined rate of Ian and Kyandre when working together?

The combined rate of Ian and Kyandre is 8/15 lawns per hour.

Q: How long does it take Ian and Kyandre to rake and bag a lawn together?

It takes them 1 hour and 52.5 minutes (or 1 and 7/8 hours) to rake and bag a lawn together.

Summary & Key Takeaways

• Ian can rake and bag a lawn in 5 hours, equivalent to a rate of 1/5 lawn per hour.

• Kyandre can do the same task in 3 hours, equivalent to a rate of 1/3 lawn per hour.

• When working together, their combined rate is 8/15 lawns per hour.