Finding the Fourth Proportional to 138.53, 207.99 and 77.70
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Solution
The fourth proportional to 138.53, 207.99 and 77.70 is: 116.66
Step by Step Solution
- Step 1: Write the proportion equation
138.53 : 207.99 = 77.70 : x - Step 2: Convert to fraction form
138.53/207.99 = 77.70/x - Step 3: Cross multiply
138.53x = 207.99 × 77.70 - Step 4: Simplify right side
138.53x = 16,161.60 - Step 5: Solve for x
x = 16,161.60/138.53 - Step 6: Final answer
x = 116.66
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These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.