Finding the Fourth Proportional to 84.12, 125.67 and 77.28
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Solution
The fourth proportional to 84.12, 125.67 and 77.28 is: 115.45
Step by Step Solution
- Step 1: Write the proportion equation
84.12 : 125.67 = 77.28 : x - Step 2: Convert to fraction form
84.12/125.67 = 77.28/x - Step 3: Cross multiply
84.12x = 125.67 × 77.28 - Step 4: Simplify right side
84.12x = 9,711.78 - Step 5: Solve for x
x = 9,711.78/84.12 - Step 6: Final answer
x = 115.45
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Why These Related Problems?
These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.