Finding the Fourth Proportional to 81.60, 122.08 and 68.79
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Solution
The fourth proportional to 81.60, 122.08 and 68.79 is: 102.92
Step by Step Solution
- Step 1: Write the proportion equation
81.60 : 122.08 = 68.79 : x - Step 2: Convert to fraction form
81.60/122.08 = 68.79/x - Step 3: Cross multiply
81.60x = 122.08 × 68.79 - Step 4: Simplify right side
81.60x = 8,397.88 - Step 5: Solve for x
x = 8,397.88/81.60 - Step 6: Final answer
x = 102.92
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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.