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Finding the Fourth Proportional to 638.24, 955.20 and 515.12

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Solution

The fourth proportional to 638.24, 955.20 and 515.12 is: 770.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.24 : 955.20 = 515.12 : x
  2. Step 2: Convert to fraction form
    638.24/955.20 = 515.12/x
  3. Step 3: Cross multiply
    638.24x = 955.20 × 515.12
  4. Step 4: Simplify right side
    638.24x = 492,042.62
  5. Step 5: Solve for x
    x = 492,042.62/638.24
  6. Step 6: Final answer
    x = 770.94

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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.