Finding the Fourth Proportional to 81.18, 121.68 and 55.49
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Solution
The fourth proportional to 81.18, 121.68 and 55.49 is: 83.17
Step by Step Solution
- Step 1: Write the proportion equation
81.18 : 121.68 = 55.49 : x - Step 2: Convert to fraction form
81.18/121.68 = 55.49/x - Step 3: Cross multiply
81.18x = 121.68 × 55.49 - Step 4: Simplify right side
81.18x = 6,751.41 - Step 5: Solve for x
x = 6,751.41/81.18 - Step 6: Final answer
x = 83.17
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Why These Related Problems?
These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.