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Finding the Fourth Proportional to 178.90, 268.14 and 86.30

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Solution

The fourth proportional to 178.90, 268.14 and 86.30 is: 129.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    178.90 : 268.14 = 86.30 : x
  2. Step 2: Convert to fraction form
    178.90/268.14 = 86.30/x
  3. Step 3: Cross multiply
    178.90x = 268.14 × 86.30
  4. Step 4: Simplify right side
    178.90x = 23,140.48
  5. Step 5: Solve for x
    x = 23,140.48/178.90
  6. Step 6: Final answer
    x = 129.35

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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.