Question

If 5/x = 15/x+20, what is the value of x/5?

Answer 1

Answer:

c) 2

Step-by-step explanation:

here you can use cross multiplication. that's where you turn the fraction into an equation. ( there's videos about it, I'm not very good at explaining )

so you can turn

$\frac{5}{x} = \frac{15}{x + 20}$

into

5(x + 20) = 15x

5x + 100 = 15x

subtract 5x from both sides

100 = 10x

x = 10.

the value of x/5 would be 2, since 10/5 is 2.

Answer 2

Since x/5 is the reciprocal of 5/x, we know that we can flip the fraction on the right hand side will be flipped.

Thus, x/5 = (x + 20)/15

Now we cross multiply, 15x = 5(x + 20)

Simplify: 15x = 5x + 100

Subtract 5x from each side: 10x = 100

Divide 10: x = 10

Now plug 10 back into the right hand side: (10 + 20)/15

So, the answer is 2.