KarlyBertrand643 KarlyBertrand643

16-03-2015
Mathematics

Answered

It takes Ralph 12 hours to paint a fence alone. Lisa can do the same job in 15 hours. If Ralph paints alone for 40 minutes before Lisa begins helping, how long must they work together to finish painting the fence? Give your answer as a simplified fraction.

Answer :

Hippalectryon Hippalectryon

16-03-2015

After 40 minutes, Ralph has already painted (40/60)/12=1/18 of the fence

Lisa's speed is 1/15 fence/hour, Ralph's speed is 1/12 fence/hour, hence when they help each other their combined speed is 1/15+1/12=3/20

Thus we need to solve 3/20*x=17/18 thus x=170/27 hours (approx 6 hours 15 mins)

Answer Link

Other Questions

During resistance exercise, muscles areA. working against a force B. repeatedly contracted C. concerted in movement D. all of the above Please select the be

There are three types of informative speeches: definition, description, and developing.Please select the best answer from the choices provided:A. True B. False

Suppose [tex]\(\int_1^3 f(x) \, dx = 5\)[/tex], [tex]\(\int_3^8 f(x) \, dx = -4\)[/tex], and [tex]\(\int_3^8 g(x) \, dx = 6\)[/tex]. Evaluate the integrals in p

Evaluate [tex]\((49)^{\frac{1}{3}}\)[/tex].

Add [tex]\( -\frac{4}{y} + \left( -\frac{7}{8y} \right) \)[/tex]:A. [tex]\( -\frac{15}{2y} \)[/tex]B. [tex]\( \frac{-32 - 7y}{8y} \)[/tex]C. [tex]\( -\frac{39}{

According to the old man, what is the world's greatest lie?A. The world's greatest lie is that people's lives are controlled by fate.B. The world's greatest lie

During the reaction, the water temperature rises from [tex]$25.00^{\circ}C$[/tex] to [tex]$28.54^{\circ}C$[/tex].The heat capacity of the calorimeter, including

Assume that when human resource managers are randomly selected, 54% say job applicants should follow up within two weeks. If 8 human resource managers are rando

I am a father who is helping his daughter pay off her student loan of $50,000. That is a lot of money; however, it is a drop in the student-loan bucket that cur

Which factor most directly contributes to the severity of a fatal traffic accident on a highway?A) Road conditionsB) Vehicle speedC) Time of dayD) Weather condi

i have 3 hundreds 17 tens 13 ones 1 tenths and 2 hundredths

Which statement accurately describes classical Greek drama? A. Plays were performed in large, outdoor theaters for enthusiastic crowds. B. Greek playwrights avo

Following the Civil War, Southern states passed laws severely restricting the rights of African-Americans. These laws varied from state to state and included th

How were the purpose of missionaries in the Oregon Territory different from those of previous Americans in the region???? Can Someone Please Help Me

What is the name of the English poet who supported Greece’s revolt against the Ottomans? A. Byron B. Wordsworth C. Goethe D. Shelley

seven halves is equal to how many wholes?

Which of the following correctly describes how most of the television shows of the '50s and '60s portrayed middle-class white women? A. Many were discontented w

Two carts collide on a level, friction-less track. Cart A has a mass of 200 g and is initially stationary. Cart B has a mass of 100 g and is initially moving wi

3x+2 solve for inverse

Dave scored 168 points in basketball he scored 147 of those points in regular season and the rest were scored in his playoff game what percent of his total poin