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3 years ago

Marta can vacuum the house in 30 min. It takes her daughter 45 min to vacuum the house. How long would it take them if they

Mathematics

1 answer:

Mamont248 [21]3 years ago

8 0

Answer:

Step-by-step explanation:

This problem is on combined work rate

given that

Marta can vacuum the house in 30 min

then her rate= 1/30

Also, her daughter will take 45 min to vacuum the house

her daughter's rate will be = 1/45

then the combined work rate is

1/30+1/45=1/T

30+45/30*45=1/T

75/1350= 1/T

1/18=1/T

This means that they will both take 18 minutes working together to vacum a house

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3 years ago

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3 years ago