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Finding the Fourth Proportional to 628.90, 943.39 and 212.41

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Solution

The fourth proportional to 628.90, 943.39 and 212.41 is: 318.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.90 : 943.39 = 212.41 : x
  2. Step 2: Convert to fraction form
    628.90/943.39 = 212.41/x
  3. Step 3: Cross multiply
    628.90x = 943.39 × 212.41
  4. Step 4: Simplify right side
    628.90x = 200,381.01
  5. Step 5: Solve for x
    x = 200,381.01/628.90
  6. Step 6: Final answer
    x = 318.62

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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.