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Finding the Fourth Proportional to 509.20, 758.45 and 485.50

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Solution

The fourth proportional to 509.20, 758.45 and 485.50 is: 723.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.20 : 758.45 = 485.50 : x
  2. Step 2: Convert to fraction form
    509.20/758.45 = 485.50/x
  3. Step 3: Cross multiply
    509.20x = 758.45 × 485.50
  4. Step 4: Simplify right side
    509.20x = 368,227.48
  5. Step 5: Solve for x
    x = 368,227.48/509.20
  6. Step 6: Final answer
    x = 723.15

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.