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Finding the Fourth Proportional to 391.68, 540.73 and 286.66

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Solution

The fourth proportional to 391.68, 540.73 and 286.66 is: 395.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.68 : 540.73 = 286.66 : x
  2. Step 2: Convert to fraction form
    391.68/540.73 = 286.66/x
  3. Step 3: Cross multiply
    391.68x = 540.73 × 286.66
  4. Step 4: Simplify right side
    391.68x = 155,005.66
  5. Step 5: Solve for x
    x = 155,005.66/391.68
  6. Step 6: Final answer
    x = 395.75

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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.