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Finding the Fourth Proportional to 391.59, 587.66 and 209.12

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Solution

The fourth proportional to 391.59, 587.66 and 209.12 is: 313.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.59 : 587.66 = 209.12 : x
  2. Step 2: Convert to fraction form
    391.59/587.66 = 209.12/x
  3. Step 3: Cross multiply
    391.59x = 587.66 × 209.12
  4. Step 4: Simplify right side
    391.59x = 122,887.48
  5. Step 5: Solve for x
    x = 122,887.48/391.59
  6. Step 6: Final answer
    x = 313.82

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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.