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Finding the Fourth Proportional to 83.63, 125.15 and 72.80

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Solution

The fourth proportional to 83.63, 125.15 and 72.80 is: 108.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    83.63 : 125.15 = 72.80 : x
  2. Step 2: Convert to fraction form
    83.63/125.15 = 72.80/x
  3. Step 3: Cross multiply
    83.63x = 125.15 × 72.80
  4. Step 4: Simplify right side
    83.63x = 9,110.40
  5. Step 5: Solve for x
    x = 9,110.40/83.63
  6. Step 6: Final answer
    x = 108.93

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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.