I will give a medal who answers this and fan them
It takes Brian 15 hours longer to build a model car than it takes John. If they work together, they can build the model car in 4 hours. Using complete sentences, explain each step in figuring out how to determine the time it would take Brian to build the car on his own

Question

I will give a medal who answers this and fan them
It takes Brian 15 hours longer to build a model car than it takes John. If they work together, they can build the model car in 4 hours. Using complete sentences, explain each step in figuring out how to determine the time it would take Brian to build the car on his own

jim_thompson5910 · Answer

x = time it takes for Brian to build the model car on his own
y = time it takes for John to build the model car on his own


we're told that `It takes Brian 15 hours longer to build a model car than it takes John` so x = y+15


$$\large \frac{1}{\text{Brian's Time}}+\frac{1}{\text{John's Time}} = \frac{1}{\text{Time if they work together}}$$

$$\large \frac{1}{x}+\frac{1}{y} = \frac{1}{4}$$

$$\large \frac{1}{y+15}+\frac{1}{y} = \frac{1}{4}$$

Do you know how to solve for y from here?

anonymous · Answer

No im so sorry this isn't my strongest subject.

jim_thompson5910 · Answer

what is the LCD of all the fractions?

anonymous · Answer

Wouldn't it be 1?

jim_thompson5910 · Answer

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