Finding the Fourth Proportional to 138.81, 207.08 and 121.71
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Solution
The fourth proportional to 138.81, 207.08 and 121.71 is: 181.57
Step by Step Solution
- Step 1: Write the proportion equation
138.81 : 207.08 = 121.71 : x - Step 2: Convert to fraction form
138.81/207.08 = 121.71/x - Step 3: Cross multiply
138.81x = 207.08 × 121.71 - Step 4: Simplify right side
138.81x = 25,203.10 - Step 5: Solve for x
x = 25,203.10/138.81 - Step 6: Final answer
x = 181.57
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These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.