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Finding the Fourth Proportional to 426.10, 639.26 and 217.36

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Solution

The fourth proportional to 426.10, 639.26 and 217.36 is: 326.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.10 : 639.26 = 217.36 : x
  2. Step 2: Convert to fraction form
    426.10/639.26 = 217.36/x
  3. Step 3: Cross multiply
    426.10x = 639.26 × 217.36
  4. Step 4: Simplify right side
    426.10x = 138,949.55
  5. Step 5: Solve for x
    x = 138,949.55/426.10
  6. Step 6: Final answer
    x = 326.10

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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.