There 27

There are 24 colored cubes in a box. Three-quarters of the cubes are red, four of the cubes are blue, and the rest are green. How many green cubes are in the box? One more blue cube got put into the box. What fraction of the cubes in the box are blue?

Correct answer:

g =  2
f =  1/5

Step-by-step explanation:

$$\begin{gathered} n=24 \\ r=\frac{3}{4}\cdot n=\frac{3}{4}\cdot 24=\frac{3\cdot 24}{4}=\frac{72}{4}=18 \\ b=4 \\ g=n-r-b=24-18-4=2 \end{gathered}$$

$f=\frac{b+1}{n+1}=\frac{4+1}{24+1}=\frac{1}{5}=0.2$

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