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Finding the Fourth Proportional to 638.80, 958.08 and 313.96

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Solution

The fourth proportional to 638.80, 958.08 and 313.96 is: 470.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.80 : 958.08 = 313.96 : x
  2. Step 2: Convert to fraction form
    638.80/958.08 = 313.96/x
  3. Step 3: Cross multiply
    638.80x = 958.08 × 313.96
  4. Step 4: Simplify right side
    638.80x = 300,798.80
  5. Step 5: Solve for x
    x = 300,798.80/638.80
  6. Step 6: Final answer
    x = 470.88

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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.