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Finding the Fourth Proportional to 83.79, 125.79 and 66.78

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Solution

The fourth proportional to 83.79, 125.79 and 66.78 is: 100.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    83.79 : 125.79 = 66.78 : x
  2. Step 2: Convert to fraction form
    83.79/125.79 = 66.78/x
  3. Step 3: Cross multiply
    83.79x = 125.79 × 66.78
  4. Step 4: Simplify right side
    83.79x = 8,400.26
  5. Step 5: Solve for x
    x = 8,400.26/83.79
  6. Step 6: Final answer
    x = 100.25

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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.