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Finding the Fourth Proportional to 281.30, 421.40 and 220.14

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Solution

The fourth proportional to 281.30, 421.40 and 220.14 is: 329.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.30 : 421.40 = 220.14 : x
  2. Step 2: Convert to fraction form
    281.30/421.40 = 220.14/x
  3. Step 3: Cross multiply
    281.30x = 421.40 × 220.14
  4. Step 4: Simplify right side
    281.30x = 92,765.90
  5. Step 5: Solve for x
    x = 92,765.90/281.30
  6. Step 6: Final answer
    x = 329.78

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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.