If sally can type a certain number of mailing labels in 6 hours and eric and sue working together can type the same number of mailing lables in 4 hours, find how long it takes eric alone to type the mailing labels.

Assume there are N labels.

Sally mails S labels/h
Eric labels E labels/h

6 S = N
4 S + 4 E = N
4S + 4 E = 6 S
2 S = 4 E
S = 2 E
E is half as fast as S, and woul;d take 12 hours alone.

thanks drwls!

are you available to answer one right now?

Alex can run 5 miles per hour on levelground on a still day. One windy day he runs 11 miles with the wind, and in the same amount of time runs 4 miles against the wind. What is the rate of the wind?

Read the second bullet point on the first page, in the bold and italics, at the end of the second sentence.

I seriously, seriously hope you weren't dumb enough to use your real first name. Mine definitely isn't Serj.

time = distance/rate and you set the rate up as (5+x) and (5-x) where x is the wind rate. The distance is obvious. solve for x.

To solve this problem, we can set up a system of equations:

Let's say Sally's typing speed is x mailing labels per hour.

Sally's work rate can be expressed as: 1/(6 hours) * x mailing labels per hour.

Eric and Sue's work rate, working together, can be expressed as: 1/(4 hours) * x mailing labels per hour.

Eric's work rate, working alone, can be expressed as: 1/(E hours) * x mailing labels per hour, where E represents the time it takes Eric alone to type the mailing labels.

Based on the given information, we know that Sally's work rate is equal to Eric and Sue's work rate. Therefore, we have the following equation:

1/(6 hours) * x mailing labels per hour = 1/(4 hours) * x mailing labels per hour

To find how long it takes Eric alone to type the mailing labels (E), we need to solve for E.

By cross-multiplying and simplifying the equation, we get:

(1/6) * x = (1/4) * x

Multiplying both sides of the equation by 12 (the least common denominator of 6 and 4), we have:

2x = 3x

Subtracting 2x from both sides, we get:

0 = x

This implies that x, which represents the typing speed, is zero. However, since typing speed cannot be zero, there is no solution to this problem.

Therefore, we can conclude that it is not possible to determine how long it takes Eric alone to type the mailing labels based on the given information.