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Finding the Fourth Proportional to 638.04, 955.68 and 393.80

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Solution

The fourth proportional to 638.04, 955.68 and 393.80 is: 589.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.04 : 955.68 = 393.80 : x
  2. Step 2: Convert to fraction form
    638.04/955.68 = 393.80/x
  3. Step 3: Cross multiply
    638.04x = 955.68 × 393.80
  4. Step 4: Simplify right side
    638.04x = 376,346.78
  5. Step 5: Solve for x
    x = 376,346.78/638.04
  6. Step 6: Final answer
    x = 589.85

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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.