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Finding the Fourth Proportional to 426.70, 640.05 and 210.43

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Solution

The fourth proportional to 426.70, 640.05 and 210.43 is: 315.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.70 : 640.05 = 210.43 : x
  2. Step 2: Convert to fraction form
    426.70/640.05 = 210.43/x
  3. Step 3: Cross multiply
    426.70x = 640.05 × 210.43
  4. Step 4: Simplify right side
    426.70x = 134,685.72
  5. Step 5: Solve for x
    x = 134,685.72/426.70
  6. Step 6: Final answer
    x = 315.65

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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.