Swimming pool

A swimming pool 30 meters long is filled with water to a depth of 1 meter at the shallow end, and 5 meters at the deep end, and abcd the vertical area of the pool has the shape of a trapezium with the area given by S(abcd)= 1/2 (ab + cd) x ad. What is the area of cross-section abcd?

Correct answer:

S =  90 m²

Step-by-step explanation:

$$\begin{gathered} AD=30\text{m} \\ AB=1\text{m} \\ CD=5\text{m} \\ S=\frac{AB+CD}{2}\cdot AD=\frac{1+5}{2}\cdot 30=90{\text{m}}^2 \end{gathered}$$

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