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Finding the Fourth Proportional to 423.26, 634.05 and 258.78

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Solution

The fourth proportional to 423.26, 634.05 and 258.78 is: 387.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    423.26 : 634.05 = 258.78 : x
  2. Step 2: Convert to fraction form
    423.26/634.05 = 258.78/x
  3. Step 3: Cross multiply
    423.26x = 634.05 × 258.78
  4. Step 4: Simplify right side
    423.26x = 164,079.46
  5. Step 5: Solve for x
    x = 164,079.46/423.26
  6. Step 6: Final answer
    x = 387.66

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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.