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Finding the Fourth Proportional to 391.24, 587.12 and 208.76

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Solution

The fourth proportional to 391.24, 587.12 and 208.76 is: 313.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.24 : 587.12 = 208.76 : x
  2. Step 2: Convert to fraction form
    391.24/587.12 = 208.76/x
  3. Step 3: Cross multiply
    391.24x = 587.12 × 208.76
  4. Step 4: Simplify right side
    391.24x = 122,567.17
  5. Step 5: Solve for x
    x = 122,567.17/391.24
  6. Step 6: Final answer
    x = 313.28

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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.