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Finding the Fourth Proportional to 70.38, 105.12 and 52.20

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Solution

The fourth proportional to 70.38, 105.12 and 52.20 is: 77.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.38 : 105.12 = 52.20 : x
  2. Step 2: Convert to fraction form
    70.38/105.12 = 52.20/x
  3. Step 3: Cross multiply
    70.38x = 105.12 × 52.20
  4. Step 4: Simplify right side
    70.38x = 5,487.26
  5. Step 5: Solve for x
    x = 5,487.26/70.38
  6. Step 6: Final answer
    x = 77.97

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.