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Finding the Fourth Proportional to 140.78, 210.56 and 82.86

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Solution

The fourth proportional to 140.78, 210.56 and 82.86 is: 123.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    140.78 : 210.56 = 82.86 : x
  2. Step 2: Convert to fraction form
    140.78/210.56 = 82.86/x
  3. Step 3: Cross multiply
    140.78x = 210.56 × 82.86
  4. Step 4: Simplify right side
    140.78x = 17,446.59
  5. Step 5: Solve for x
    x = 17,446.59/140.78
  6. Step 6: Final answer
    x = 123.93

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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.