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Finding the Fourth Proportional to 509.70, 763.20 and 400.80

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Solution

The fourth proportional to 509.70, 763.20 and 400.80 is: 600.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.70 : 763.20 = 400.80 : x
  2. Step 2: Convert to fraction form
    509.70/763.20 = 400.80/x
  3. Step 3: Cross multiply
    509.70x = 763.20 × 400.80
  4. Step 4: Simplify right side
    509.70x = 305,890.56
  5. Step 5: Solve for x
    x = 305,890.56/509.70
  6. Step 6: Final answer
    x = 600.14

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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.