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Finding the Fourth Proportional to 521.71, 720.04 and 311.82

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Solution

The fourth proportional to 521.71, 720.04 and 311.82 is: 430.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.71 : 720.04 = 311.82 : x
  2. Step 2: Convert to fraction form
    521.71/720.04 = 311.82/x
  3. Step 3: Cross multiply
    521.71x = 720.04 × 311.82
  4. Step 4: Simplify right side
    521.71x = 224,523.65
  5. Step 5: Solve for x
    x = 224,523.65/521.71
  6. Step 6: Final answer
    x = 430.36

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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.