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Finding the Fourth Proportional to 73.12, 109.80 and 67.78

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Solution

The fourth proportional to 73.12, 109.80 and 67.78 is: 101.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    73.12 : 109.80 = 67.78 : x
  2. Step 2: Convert to fraction form
    73.12/109.80 = 67.78/x
  3. Step 3: Cross multiply
    73.12x = 109.80 × 67.78
  4. Step 4: Simplify right side
    73.12x = 7,442.24
  5. Step 5: Solve for x
    x = 7,442.24/73.12
  6. Step 6: Final answer
    x = 101.78

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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.