College Math Placement Test 2025 – 400 Free Practice Questions to Pass the Exam

Question: 1 / 400

What is the length of the other base of a trapezoid with an area of 864 cm², height of 24 cm, and one base length of 30 cm?

42 cm

To find the length of the other base of the trapezoid, we can use the formula for the area of a trapezoid:

\text{Area} = \frac{1}{2} \times (b_1 + b_2) \times h

where $b_1$ and $b_2$ are the lengths of the two bases, and $h$ is the height. We know the area (864 cm²), the height (24 cm), and one base (30 cm).

First, we can rearrange the formula to solve for the sum of the bases:

864 = \frac{1}{2} \times (30 + b_2) \times 24

Multiplying both sides by 2 to eliminate the fraction gives:

1728 = (30 + b_2) \times 24

Next, divide both sides by 24 to isolate the term with the bases:

72 = 30 + b_2

To find $b_2$, subtract 30 from both sides:

b_2 = 72 - 30 = 42 \text{

45 cm

114 cm

38 cm

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