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Finding the Fourth Proportional to 391.77, 540.02 and 286.86

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Solution

The fourth proportional to 391.77, 540.02 and 286.86 is: 395.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.77 : 540.02 = 286.86 : x
  2. Step 2: Convert to fraction form
    391.77/540.02 = 286.86/x
  3. Step 3: Cross multiply
    391.77x = 540.02 × 286.86
  4. Step 4: Simplify right side
    391.77x = 154,910.14
  5. Step 5: Solve for x
    x = 154,910.14/391.77
  6. Step 6: Final answer
    x = 395.41

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.