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Finding the Fourth Proportional to 97.80, 134.96 and 62.78

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Solution

The fourth proportional to 97.80, 134.96 and 62.78 is: 86.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    97.80 : 134.96 = 62.78 : x
  2. Step 2: Convert to fraction form
    97.80/134.96 = 62.78/x
  3. Step 3: Cross multiply
    97.80x = 134.96 × 62.78
  4. Step 4: Simplify right side
    97.80x = 8,472.79
  5. Step 5: Solve for x
    x = 8,472.79/97.80
  6. Step 6: Final answer
    x = 86.63

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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.