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Finding the Fourth Proportional to 638.46, 955.80 and 394.20

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Solution

The fourth proportional to 638.46, 955.80 and 394.20 is: 590.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.46 : 955.80 = 394.20 : x
  2. Step 2: Convert to fraction form
    638.46/955.80 = 394.20/x
  3. Step 3: Cross multiply
    638.46x = 955.80 × 394.20
  4. Step 4: Simplify right side
    638.46x = 376,776.36
  5. Step 5: Solve for x
    x = 376,776.36/638.46
  6. Step 6: Final answer
    x = 590.13

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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.