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Finding the Fourth Proportional to 281.80, 421.80 and 255.16

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Solution

The fourth proportional to 281.80, 421.80 and 255.16 is: 381.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.80 : 421.80 = 255.16 : x
  2. Step 2: Convert to fraction form
    281.80/421.80 = 255.16/x
  3. Step 3: Cross multiply
    281.80x = 421.80 × 255.16
  4. Step 4: Simplify right side
    281.80x = 107,626.49
  5. Step 5: Solve for x
    x = 107,626.49/281.80
  6. Step 6: Final answer
    x = 381.93

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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.