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Finding the Fourth Proportional to 78.14, 107.87 and 53.71

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Solution

The fourth proportional to 78.14, 107.87 and 53.71 is: 74.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.14 : 107.87 = 53.71 : x
  2. Step 2: Convert to fraction form
    78.14/107.87 = 53.71/x
  3. Step 3: Cross multiply
    78.14x = 107.87 × 53.71
  4. Step 4: Simplify right side
    78.14x = 5,793.16
  5. Step 5: Solve for x
    x = 5,793.16/78.14
  6. Step 6: Final answer
    x = 74.14

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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.