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Finding the Fourth Proportional to 426.75, 640.58 and 210.79

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Solution

The fourth proportional to 426.75, 640.58 and 210.79 is: 316.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.75 : 640.58 = 210.79 : x
  2. Step 2: Convert to fraction form
    426.75/640.58 = 210.79/x
  3. Step 3: Cross multiply
    426.75x = 640.58 × 210.79
  4. Step 4: Simplify right side
    426.75x = 135,027.86
  5. Step 5: Solve for x
    x = 135,027.86/426.75
  6. Step 6: Final answer
    x = 316.41

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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.