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Finding the Fourth Proportional to 67.39, 101.65 and 64.78

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Solution

The fourth proportional to 67.39, 101.65 and 64.78 is: 97.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    67.39 : 101.65 = 64.78 : x
  2. Step 2: Convert to fraction form
    67.39/101.65 = 64.78/x
  3. Step 3: Cross multiply
    67.39x = 101.65 × 64.78
  4. Step 4: Simplify right side
    67.39x = 6,584.89
  5. Step 5: Solve for x
    x = 6,584.89/67.39
  6. Step 6: Final answer
    x = 97.71

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.