It takes an older computer 3 times as long to send out a company's email as it does a newer computer. Working together, it takes the two computers minutes to send out the email. How long will it take the older computer to send out the email on its own?
Do not do any rounding.
Let x be the time it takes the newer computer to send out the email on its own.
Since the older computer takes 3 times as long, it will take 3x minutes on its own.
Working together, they can send out the email in 20 minutes, so their combined work rate is 1/20 of the job per minute.
The work rate of the newer computer is 1/x and the work rate of the older computer is 1/3x.
Therefore, we can set up the equation:
1/x + 1/3x = 1/20
Multiplying by 60x to clear the fractions, we get:
60 + 20 = 3x
80 = 3x
x = 80/3 = 26.6 repeating
So the time it takes the newer computer to send out the email on its own is 26.6 repeating minutes.
Therefore, the time it takes the older computer to send out the email on its own is 3 times as long, which is:
3 * 26.6 repeating = 79.9 repeating
Therefore, it takes the older computer approximately 79.9 repeating minutes to send out the email on its own.