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Finding the Fourth Proportional to 391.08, 587.10 and 247.40

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Solution

The fourth proportional to 391.08, 587.10 and 247.40 is: 371.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.08 : 587.10 = 247.40 : x
  2. Step 2: Convert to fraction form
    391.08/587.10 = 247.40/x
  3. Step 3: Cross multiply
    391.08x = 587.10 × 247.40
  4. Step 4: Simplify right side
    391.08x = 145,248.54
  5. Step 5: Solve for x
    x = 145,248.54/391.08
  6. Step 6: Final answer
    x = 371.40

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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.