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Finding the Fourth Proportional to 61.38, 84.64 and 39.51

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Solution

The fourth proportional to 61.38, 84.64 and 39.51 is: 54.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    61.38 : 84.64 = 39.51 : x
  2. Step 2: Convert to fraction form
    61.38/84.64 = 39.51/x
  3. Step 3: Cross multiply
    61.38x = 84.64 × 39.51
  4. Step 4: Simplify right side
    61.38x = 3,344.13
  5. Step 5: Solve for x
    x = 3,344.13/61.38
  6. Step 6: Final answer
    x = 54.48

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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.