Help with practice quiz-math question.?

Sally paints 1/4 of the house in an hour and John paints 1/6 of the house in an hour. 1/4+1/6 = 3/12+2/12 = 5/12 so working together they paint 5/12 of the house in an hour. So it takes them 12/5 hours to paint it. 12/5=2 & 2/5 and since 2/5 hour is 24 minutes the answer you want is A.

Of course, in practice, it will be slower with two people because they'll stop and have a chat.

I hope this helps.

In 1 hour Sally can paint 1/4 of the house;

In 1 hour John can paint 1/6 of the house;

In 1 hour they together can paint 1/4 + 1/6 = 5/12 of the house.

1 hour = 60 minutes

60 : 5/12 = x : 1

x = 60 : 5/12 = 60*12/5 = 144 minutes = 2 hours and 24 minutes.

A. 2 hours and 24 minutes

Bye

gilvi

sally can paint one house in 4 hours

which means she can paint 1/4th of a house in an hour

similarly, john can paint 1/6th of a house in an hour

together, they can paint (1/4) + (1/6) of the house in one hour..

1/4 + 1/6 = 5/12

they can paint 5/12 of the house in one hour

now use unitary method..

5/12 house <--- 1 hour

1 house ---> ? hours

? = 1*1 / (5/12)

= 12/5

= 2.4 hours

which is 2 hours 24 mins

20% off potential you're paying one hundred - 20 = 80% of the unique cost. 20% = .20 permit x = unique cost (a million - .20)x = 12,590 .8x = 12,590 x = 12,590/.8 = $15,737.50 D. $15,737.50