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Finding the Fourth Proportional to 509.85, 764.98 and 201.78

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Solution

The fourth proportional to 509.85, 764.98 and 201.78 is: 302.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.85 : 764.98 = 201.78 : x
  2. Step 2: Convert to fraction form
    509.85/764.98 = 201.78/x
  3. Step 3: Cross multiply
    509.85x = 764.98 × 201.78
  4. Step 4: Simplify right side
    509.85x = 154,357.16
  5. Step 5: Solve for x
    x = 154,357.16/509.85
  6. Step 6: Final answer
    x = 302.75

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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.