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Finding the Fourth Proportional to 61.78, 85.24 and 37.21

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Solution

The fourth proportional to 61.78, 85.24 and 37.21 is: 51.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    61.78 : 85.24 = 37.21 : x
  2. Step 2: Convert to fraction form
    61.78/85.24 = 37.21/x
  3. Step 3: Cross multiply
    61.78x = 85.24 × 37.21
  4. Step 4: Simplify right side
    61.78x = 3,171.17
  5. Step 5: Solve for x
    x = 3,171.17/61.78
  6. Step 6: Final answer
    x = 51.33

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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.