Question

Let's say you are in Monument Valley and decided to measure the height of a rock formation using the method you learned from the workbook. The distance from your eyes to your finger is 21 inches. When you look through your fingers at the rock, the gap between your fingers is 3 4 of an inch. You know that you are about 5 miles from the rock. According to this information, approximately how tall is that rock formation? Find your answer in miles (round your answer to the nearest hundredth), then convert it to feet (round it to the nearest tenth).

Answer 1

height = 0.18 mi, 942.9 feet

Explanation:

Using the formula

Distance between fingers / Distance between fingers and eye = height of object / distance between person and object

Hence (3/4 inch)/ 21 inches = height of object/5 miles

Solving for height of the object, we obtain

height of the object = 0.18 mi

in feet, height = 0.18 * 5280 (1 mile = 5280 ft)

Hence height = 942.9 feet