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Finding the Fourth Proportional to 73.78, 102.31 and 71.53

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Solution

The fourth proportional to 73.78, 102.31 and 71.53 is: 99.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    73.78 : 102.31 = 71.53 : x
  2. Step 2: Convert to fraction form
    73.78/102.31 = 71.53/x
  3. Step 3: Cross multiply
    73.78x = 102.31 × 71.53
  4. Step 4: Simplify right side
    73.78x = 7,318.23
  5. Step 5: Solve for x
    x = 7,318.23/73.78
  6. Step 6: Final answer
    x = 99.19

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.