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Finding the Fourth Proportional to 42.12, 63.10 and 38.80

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Solution

The fourth proportional to 42.12, 63.10 and 38.80 is: 58.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    42.12 : 63.10 = 38.80 : x
  2. Step 2: Convert to fraction form
    42.12/63.10 = 38.80/x
  3. Step 3: Cross multiply
    42.12x = 63.10 × 38.80
  4. Step 4: Simplify right side
    42.12x = 2,448.28
  5. Step 5: Solve for x
    x = 2,448.28/42.12
  6. Step 6: Final answer
    x = 58.13

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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.