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Finding the Fourth Proportional to 423.30, 634.65 and 217.70

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Solution

The fourth proportional to 423.30, 634.65 and 217.70 is: 326.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    423.30 : 634.65 = 217.70 : x
  2. Step 2: Convert to fraction form
    423.30/634.65 = 217.70/x
  3. Step 3: Cross multiply
    423.30x = 634.65 × 217.70
  4. Step 4: Simplify right side
    423.30x = 138,163.31
  5. Step 5: Solve for x
    x = 138,163.31/423.30
  6. Step 6: Final answer
    x = 326.40

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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.