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Finding the Fourth Proportional to 502.80, 693.90 and 281.78

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Solution

The fourth proportional to 502.80, 693.90 and 281.78 is: 388.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    502.80 : 693.90 = 281.78 : x
  2. Step 2: Convert to fraction form
    502.80/693.90 = 281.78/x
  3. Step 3: Cross multiply
    502.80x = 693.90 × 281.78
  4. Step 4: Simplify right side
    502.80x = 195,527.14
  5. Step 5: Solve for x
    x = 195,527.14/502.80
  6. Step 6: Final answer
    x = 388.88

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.