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Finding the Fourth Proportional to 509.30, 762.11 and 421.82

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Solution

The fourth proportional to 509.30, 762.11 and 421.82 is: 631.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.30 : 762.11 = 421.82 : x
  2. Step 2: Convert to fraction form
    509.30/762.11 = 421.82/x
  3. Step 3: Cross multiply
    509.30x = 762.11 × 421.82
  4. Step 4: Simplify right side
    509.30x = 321,473.24
  5. Step 5: Solve for x
    x = 321,473.24/509.30
  6. Step 6: Final answer
    x = 631.21

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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.