Finding the Fourth Proportional to 81.84, 122.88 and 68.40
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Solution
The fourth proportional to 81.84, 122.88 and 68.40 is: 102.70
Step by Step Solution
- Step 1: Write the proportion equation
81.84 : 122.88 = 68.40 : x - Step 2: Convert to fraction form
81.84/122.88 = 68.40/x - Step 3: Cross multiply
81.84x = 122.88 × 68.40 - Step 4: Simplify right side
81.84x = 8,404.99 - Step 5: Solve for x
x = 8,404.99/81.84 - Step 6: Final answer
x = 102.70
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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.