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Finding the Fourth Proportional to 457.80, 686.79 and 320.88

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Solution

The fourth proportional to 457.80, 686.79 and 320.88 is: 481.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    457.80 : 686.79 = 320.88 : x
  2. Step 2: Convert to fraction form
    457.80/686.79 = 320.88/x
  3. Step 3: Cross multiply
    457.80x = 686.79 × 320.88
  4. Step 4: Simplify right side
    457.80x = 220,377.18
  5. Step 5: Solve for x
    x = 220,377.18/457.80
  6. Step 6: Final answer
    x = 481.38

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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.