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Finding the Fourth Proportional to 381.80, 570.09 and 308.90

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Solution

The fourth proportional to 381.80, 570.09 and 308.90 is: 461.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    381.80 : 570.09 = 308.90 : x
  2. Step 2: Convert to fraction form
    381.80/570.09 = 308.90/x
  3. Step 3: Cross multiply
    381.80x = 570.09 × 308.90
  4. Step 4: Simplify right side
    381.80x = 176,097.95
  5. Step 5: Solve for x
    x = 176,097.95/381.80
  6. Step 6: Final answer
    x = 461.24

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.