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Finding the Fourth Proportional to 426.29, 639.35 and 310.80

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Solution

The fourth proportional to 426.29, 639.35 and 310.80 is: 466.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.29 : 639.35 = 310.80 : x
  2. Step 2: Convert to fraction form
    426.29/639.35 = 310.80/x
  3. Step 3: Cross multiply
    426.29x = 639.35 × 310.80
  4. Step 4: Simplify right side
    426.29x = 198,708.43
  5. Step 5: Solve for x
    x = 198,708.43/426.29
  6. Step 6: Final answer
    x = 466.13

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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.