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Finding the Fourth Proportional to 102.40, 141.31 and 63.57

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Solution

The fourth proportional to 102.40, 141.31 and 63.57 is: 87.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    102.40 : 141.31 = 63.57 : x
  2. Step 2: Convert to fraction form
    102.40/141.31 = 63.57/x
  3. Step 3: Cross multiply
    102.40x = 141.31 × 63.57
  4. Step 4: Simplify right side
    102.40x = 8,982.37
  5. Step 5: Solve for x
    x = 8,982.37/102.40
  6. Step 6: Final answer
    x = 87.72

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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.