8.7 닮은 도형의 활용 문제 풀기

다음 두 문제에서는 제시된 지도를 이용하세요. 지도 위에서 샌안토니오(San Antonio), 오마하(Omaha), 콜럼버스(Columbus) 는 아래 그림과 같이 세 변으로 이루어진 삼각형을 형성합니다. 샌안토니오에서 오마하까지의 실제 거리는 802 마일입니다.

ⓐ 샌안토니오에서 콜럼버스까지의 실제 거리를 구하세요. 단, 소수점 아래 둘째 자리에서 반올림하여 소수 첫째 자리까지 나타내세요.

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1102.8  마일

Step 1 of 7

Read the problem. Draw the figures and label with the given information.

The figures are shown in the question.

Step 2 of 7

Identify what we are looking for: the actual distance from San Antonio to Columbus.

Step 3 of 7

Name the variables.

Let x = distance from San Antonio to Columbus.

Step 4 of 7

Translate into an equation. Since the triangles are similar, the corresponding sides are proportional. We’ll make the numerators "miles" and the denominators "inches."

x mi 6.6 in = 802 mi 4.8 in

Step 5 of 7

Solve the equation.

x 6.6 = 802 4.8

x = 802 · 6.6 4.8 = 1102.8 mi

Step 6 of 7

Check.

Check x = 1102.8 mi in the original proportion.

x mi 6.6 in = 802 mi2 4.8 in

1102.8 mi 6.6 in = ? 802 mi 4.8 in

802 mi 4.8 in = ? 802 mi 4.8 in

Step 7 of 7

Answer the question.

The distance from San Antonio to Columbus is 1102.8 miles.


ⓑ Find the actual distance from Omaha to Columbus. Round your answer to the closest tenth.

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668.3  mi

Step 1 of 7

Read the problem. Draw the figures and label with the given information.

The figures are shown in the question.

Step 2 of 7

Identify what we are looking for: the actual distance from Omaha to Columbus.

Step 3 of 7

Name the variables.

Let y = distance from Omaha to Columbus.

Step 4 of 7

Translate into an equation. Since the triangles are similar, the corresponding sides are proportional. We’ll make the numerators "miles" and the denominators "inches."

y mi 4 in = 802 mi 4.8 in

Step 5 of 7

Solve the equation.

y 4 = 802 4.8

y = 802 · 4 4.8 = 668.3 mi

Step 6 of 7

Check.

Check y = 668.3 mi in the original proportion.

y mi 4 in = 802 mi2 4.8 in

668.3 mi 4 in = ? 802 mi 4.8 in

802 mi 4.8 in = ? 802 mi 4.8 in

Step 7 of 7

Answer the question.

The distance from Omaha to Columbus is 668.3 miles.