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Finding the Fourth Proportional to 82.71, 124.05 and 53.78

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Solution

The fourth proportional to 82.71, 124.05 and 53.78 is: 80.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    82.71 : 124.05 = 53.78 : x
  2. Step 2: Convert to fraction form
    82.71/124.05 = 53.78/x
  3. Step 3: Cross multiply
    82.71x = 124.05 × 53.78
  4. Step 4: Simplify right side
    82.71x = 6,670.79
  5. Step 5: Solve for x
    x = 6,670.79/82.71
  6. Step 6: Final answer
    x = 80.65

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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.