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Finding the Fourth Proportional to 73.78, 101.21 and 71.96

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Solution

The fourth proportional to 73.78, 101.21 and 71.96 is: 98.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    73.78 : 101.21 = 71.96 : x
  2. Step 2: Convert to fraction form
    73.78/101.21 = 71.96/x
  3. Step 3: Cross multiply
    73.78x = 101.21 × 71.96
  4. Step 4: Simplify right side
    73.78x = 7,282.21
  5. Step 5: Solve for x
    x = 7,282.21/73.78
  6. Step 6: Final answer
    x = 98.70

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.