Question

a pillars shadow is 18 feet long. a 4 - foot tall child standing nearby casts a shadow of 3 feet. what is the height of the pillar?

Explanation:

Step1: Set up proportion

Let the height of the pillar be $h$. Since the ratios of height to shadow - length are equal for the pillar and the child, we have the proportion $\frac{h}{18}=\frac{4}{3}$.

Step2: Cross - multiply

Cross - multiplying gives us $3h = 4\times18$.

Step3: Calculate the right - hand side

$4\times18 = 72$, so $3h=72$.

Step4: Solve for $h$

Dividing both sides of the equation $3h = 72$ by 3, we get $h=\frac{72}{3}=24$.

Answer:

24