# math

posted by .

Megan and Sam together take 12 minutes to wash a car. Washing the car by herself took Megan 21 minutes. How long would it take Sam to wash the car?

• math -

1/both = 1/megan + 1/sam
1/12 = 1/21 + 1/s
s = 28

• math -

I like chicken

## Similar Questions

1. ### Math

Vivica washhes 6 cars in 60 minutes. How many minutes does it take Vivica to wash one car?
2. ### math

Jack and Jill wash a car at the same rate . Working together it takes them an hour and 10 minutes to wash a car. One day jack started washing a car by himself at 2:30 p m. When he was half way done , Jill joined him . What time did …
3. ### math

A group of students have volunteered for the student council car wash. Janet can wash a car in m minutes. Rodrigs can wash a car in m-5 minutes, while Nick needs the same amount of time as Janet.If they all work together, they can …
4. ### algebra

frank can wash the car in 2/3 the time his younger brother,joe,can wash the car.they worked together and washed the car in 40 minutes.how long would it have taken each boy working separately?
5. ### Algebra

Evan washes two types of vehicles. It takes him 30 minutes to wash a car and 40 minutes to wash a truck. He charges \$12 to wash a car and \$15 to wash a truck. In 270 minutes, Evan made \$105 washing cars and trucks. How many trucks …
6. ### Math

Megan completes most puzzles in 24 minutes. Hassan completes most puzzles in 16 minutes. If Megan and Hassan complete a puzzle together, how long will it take?
7. ### Math

Ingrid walked her dog and washed her car . She spent 3 times as much time washing her car as she did walking her dog. it took Ingrid 1 1/2 hours to wash her car .How long did it take Ingrid to walk her dog ?
8. ### algebra 2-1

Evan washes two types of vehicles. It takes him 30 minutes to wash a car and 40 minutes to wash a truck. He charges \$12 to wash a car and \$15 to wash a truck. In 270 minutes, Evan made \$105 washing cars and trucks. How many trucks …
9. ### Math

Good evening everyone. I am very confused on how to work on the below problem. Ingrid walked her dog and washed her car. The time she spent walking her dog was 1/4 the time it took to wash her car. It took Ingrid 14 minutes to walk …
10. ### Math 253 algebra

Ann takes 2 hours to wash her car. When her sister helps her, the job takes 5/4 hours. How long does it take Ann's sister to wash the car by herself. ( Note:I created a table and gave ann a 1/2 fraction and her sister a x/1 fraction …

More Similar Questions