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Finding the Fourth Proportional to 479.20, 717.99 and 421.69

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Solution

The fourth proportional to 479.20, 717.99 and 421.69 is: 631.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    479.20 : 717.99 = 421.69 : x
  2. Step 2: Convert to fraction form
    479.20/717.99 = 421.69/x
  3. Step 3: Cross multiply
    479.20x = 717.99 × 421.69
  4. Step 4: Simplify right side
    479.20x = 302,769.20
  5. Step 5: Solve for x
    x = 302,769.20/479.20
  6. Step 6: Final answer
    x = 631.82

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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.