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Finding the Fourth Proportional to 83.52, 115.20 and 79.20

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Solution

The fourth proportional to 83.52, 115.20 and 79.20 is: 109.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    83.52 : 115.20 = 79.20 : x
  2. Step 2: Convert to fraction form
    83.52/115.20 = 79.20/x
  3. Step 3: Cross multiply
    83.52x = 115.20 × 79.20
  4. Step 4: Simplify right side
    83.52x = 9,123.84
  5. Step 5: Solve for x
    x = 9,123.84/83.52
  6. Step 6: Final answer
    x = 109.24

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.