Question

A triangle and a trapezoid are equal in area. They also have the same altitude. If the base of the triangle is $18cm$, the median of the trapezoid is

• A. $36cm$
• B. $9cm$
• C. $18cm$
• D. Not obtainable from these data
• E. None of these

Answer 1

The correct option is B $9cm$

$A=\frac{1}{2}bh=\frac{1}{2}h(b_1+b_2);\therefore b_1+b_2=b=18$.
$\therefore m=\frac{1}{2}(b_1+b_2)=9$.