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Finding the Fourth Proportional to 509.79, 763.31 and 419.58

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Solution

The fourth proportional to 509.79, 763.31 and 419.58 is: 628.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.79 : 763.31 = 419.58 : x
  2. Step 2: Convert to fraction form
    509.79/763.31 = 419.58/x
  3. Step 3: Cross multiply
    509.79x = 763.31 × 419.58
  4. Step 4: Simplify right side
    509.79x = 320,265.79
  5. Step 5: Solve for x
    x = 320,265.79/509.79
  6. Step 6: Final answer
    x = 628.24

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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.