Two friends together complete a work in (12\text{ days}). The first friend alone takes (10\text{ days}) less than the second. How many days will the first friend alone take?
Answer and explanation
Correct answer: (20\text{ days})
Let the first friend's time be (x), so the second's is (x+10), and (\frac{1}{x}+\frac{1}{x+10}=\frac{1}{12}). This gives (x^2-14x-120=0), so (x=20).
Frequently asked questions
What is the correct answer to this question?
(20\text{ days})
Why is this the correct answer?
Let the first friend's time be (x), so the second's is (x+10), and (\frac{1}{x}+\frac{1}{x+10}=\frac{1}{12}). This gives (x^2-14x-120=0), so (x=20).
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Quadratic Equations. Topic: Word Problems and Applications.
Student feedback
Was this question useful?
👍 0 Helpful 👎 0 Not helpful
Yes 0% No 0%
0 responsesStudent Reviews
No published reviews yet.