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Finding the Fourth Proportional to 509.71, 764.49 and 279.05

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Solution

The fourth proportional to 509.71, 764.49 and 279.05 is: 418.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.71 : 764.49 = 279.05 : x
  2. Step 2: Convert to fraction form
    509.71/764.49 = 279.05/x
  3. Step 3: Cross multiply
    509.71x = 764.49 × 279.05
  4. Step 4: Simplify right side
    509.71x = 213,327.11
  5. Step 5: Solve for x
    x = 213,327.11/509.71
  6. Step 6: Final answer
    x = 418.53

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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.