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Finding the Fourth Proportional to 83.12, 124.78 and 72.98

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Solution

The fourth proportional to 83.12, 124.78 and 72.98 is: 109.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    83.12 : 124.78 = 72.98 : x
  2. Step 2: Convert to fraction form
    83.12/124.78 = 72.98/x
  3. Step 3: Cross multiply
    83.12x = 124.78 × 72.98
  4. Step 4: Simplify right side
    83.12x = 9,106.44
  5. Step 5: Solve for x
    x = 9,106.44/83.12
  6. Step 6: Final answer
    x = 109.56

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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.