A rectangle 7

A rectangle has been split into 24 parts, set in 4 rows of 6 pieces each. The parts in the top 3 rows have been shaded blue. The parts in the left five columns have been shaded purple. The first five parts in the top 3 rows are striped to show they are shaded in both blue and purple. Along the top of the rectangle, the columns are labeled one-sixth. Along the left side of the rectangle, the rows are labeled one-fourth.
What is the area of the striped rectangle?

Correct answer:

S =  9

Step-by-step explanation:

$$\begin{gathered} y=4 \\ x=6 \\ S=x\cdot y-5\cdot 3=6\cdot 4-5\cdot 3=9 \end{gathered}$$

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