Finding the Fourth Proportional to 81.28, 121.96 and 63.28
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Solution
The fourth proportional to 81.28, 121.96 and 63.28 is: 94.95
Step by Step Solution
- Step 1: Write the proportion equation
81.28 : 121.96 = 63.28 : x - Step 2: Convert to fraction form
81.28/121.96 = 63.28/x - Step 3: Cross multiply
81.28x = 121.96 × 63.28 - Step 4: Simplify right side
81.28x = 7,717.63 - Step 5: Solve for x
x = 7,717.63/81.28 - Step 6: Final answer
x = 94.95
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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.