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Finding the Fourth Proportional to 426.50, 639.23 and 221.16

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Solution

The fourth proportional to 426.50, 639.23 and 221.16 is: 331.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.50 : 639.23 = 221.16 : x
  2. Step 2: Convert to fraction form
    426.50/639.23 = 221.16/x
  3. Step 3: Cross multiply
    426.50x = 639.23 × 221.16
  4. Step 4: Simplify right side
    426.50x = 141,372.11
  5. Step 5: Solve for x
    x = 141,372.11/426.50
  6. Step 6: Final answer
    x = 331.47

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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.