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Finding the Fourth Proportional to 628.34, 940.05 and 421.92

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Solution

The fourth proportional to 628.34, 940.05 and 421.92 is: 631.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.34 : 940.05 = 421.92 : x
  2. Step 2: Convert to fraction form
    628.34/940.05 = 421.92/x
  3. Step 3: Cross multiply
    628.34x = 940.05 × 421.92
  4. Step 4: Simplify right side
    628.34x = 396,625.90
  5. Step 5: Solve for x
    x = 396,625.90/628.34
  6. Step 6: Final answer
    x = 631.23

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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.