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Finding the Fourth Proportional to 647.28, 892.26 and 398.43

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Solution

The fourth proportional to 647.28, 892.26 and 398.43 is: 549.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.28 : 892.26 = 398.43 : x
  2. Step 2: Convert to fraction form
    647.28/892.26 = 398.43/x
  3. Step 3: Cross multiply
    647.28x = 892.26 × 398.43
  4. Step 4: Simplify right side
    647.28x = 355,503.15
  5. Step 5: Solve for x
    x = 355,503.15/647.28
  6. Step 6: Final answer
    x = 549.23

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.