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Finding the Fourth Proportional to 280.70, 421.14 and 136.31

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Solution

The fourth proportional to 280.70, 421.14 and 136.31 is: 204.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.70 : 421.14 = 136.31 : x
  2. Step 2: Convert to fraction form
    280.70/421.14 = 136.31/x
  3. Step 3: Cross multiply
    280.70x = 421.14 × 136.31
  4. Step 4: Simplify right side
    280.70x = 57,405.59
  5. Step 5: Solve for x
    x = 57,405.59/280.70
  6. Step 6: Final answer
    x = 204.51

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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.