Math
posted by Meghan .
One grocery clerk can stock a shelf in 40 min, whereas a second clerk requires 20 min to stock the same shelf. How long would it take to stock the shelf if the two clerks worked together?
Is this how you do this:
t/40 + t/24 =1
t*3/40*3 + t*5/24*5 =1
3t/120 + 5t/120 =1
(8t/120)*120 = 1(120)
8t/8 = 120/8
=15

Math 
Reiny
No,
rate of first = 1/40
rate of second = 1/20
combined rate = 1/40 + 1/20 = 3/40
so time for job = 1/(3/40) = 40/3 minutes
or 13 1/3 minutes
Respond to this Question
Similar Questions

Math
One grocery clerk can stock a shelf in 40 min, whereas a second clerk requires 20 min to stock the same shelf. How long would it take to stock the shelf if the two clerks worked together? 
math
you currently have 12 bottles on you shelf.and you want to keep a min of 6 bottles on you shelf.you average sales is 2 per day what is the min you would order for enough bottles for 7 days 
Math
Practice Dividing by 9 A Jeweler placed 20 necklaces on 5 different tables. He placed the same number of necklaces on each table . How many necklaces did the jeweler place on each? 
math
There are eight shelves. How many soup cans a grocery clerk stack if the bottom shelf has 21 cans and each additional shelf has 2 fewer soup cans than the previous shelf? 
math
Aubrey has a shelf full of books. • Exactly 1} 3 of the books on the shelf are mysteries. • Aubrey has read 10 of the mysteries on the shelf. • The number of mysteries Aubrey has read is greater than }1 5 of the number of mysteries … 
Algebra
How do I answer this? Robert needs to cut four shelves from a board that is 2.5 meters long. The second shelf is 18 centimeters longer than twice the length of the first shelf. The third shelf is 12 centimeters shorter than the first 
Algebra
Robert needs to cut for shelves from a board that is 2.5 m long. the second shelf is 18 cm longer than twice the length of the first shelf. the third shelf is 12 cm shorter than the first shelf. the remaining shelf is 4 cm longer than … 
math
There are 2 books on the first shelf,6books on the second shelf,12 books on the third shelf and 20 books on the the fourth shelf how many books on the tenth shelf. What do I do i need help 
Math
Dan wants to cover a Shelf with shelf liner the Shelf is 4 feet wide and 2/3 feet deep what is the area of the Shelf 
math
Two shelves contain 55 books. If half of the books from the second shelf were relocated to the first shelf, then the first shelf would contain 4 times more books than the second one. How many books are there on each shelf?