antoxavier wrote:

Diane find 2 and a half cans of paint are just enough to paint one third of her room. How many more cans of paint will she need to finish her room and paint a second room of the same size?

A. 5

B. 7 and a half

C. 10

D. 12 and a half

E. 15

Proportion with multiplier approachRemaining work = \(\frac{5}{3}\)

Let x = amount of paint needed

\(\frac{\frac{5}{2}}{\frac{1}{3}}\) = \(\frac{x}{\frac{5}{3}}\)

Use the multiplier for the denominator:

\(\frac{1}{3}\) ---> \(\frac{5}{3}\) means \(\frac{1}{3}\) was multiplied by 5.

So multiply the numerator by 5.

\(\frac{5}{2}\) * 5 = \(\frac{25}{2}\) or 12\(\frac{1}{2}\)

Answer D

Straight proportion methodRemaining work: \(\frac{5}{3}\)

Let x = amount of paint needed

\(\frac{\frac{5}{2}}{\frac{1}{3}}\) = \(\frac{x}{\frac{5}{3}}\)

\(\frac{1}{3}\)x = \(\frac{5}{2}\) * \(\frac{5}{3}\)

\(\frac{1}{3}\)x = \(\frac{25}{6}\)

x = \(\frac{25}{6}\) * 3

x = \(\frac{25}{2}\) or 12\(\frac{1}{2}\)

Answer D

_________________

In the depths of winter, I finally learned

that within me there lay an invincible summer.

-- Albert Camus, "Return to Tipasa"