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Finding the Fourth Proportional to 281.20, 421.68 and 88.78

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Solution

The fourth proportional to 281.20, 421.68 and 88.78 is: 133.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.20 : 421.68 = 88.78 : x
  2. Step 2: Convert to fraction form
    281.20/421.68 = 88.78/x
  3. Step 3: Cross multiply
    281.20x = 421.68 × 88.78
  4. Step 4: Simplify right side
    281.20x = 37,436.75
  5. Step 5: Solve for x
    x = 37,436.75/281.20
  6. Step 6: Final answer
    x = 133.13

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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.