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Finding the Fourth Proportional to 391.08, 539.81 and 243.63

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Solution

The fourth proportional to 391.08, 539.81 and 243.63 is: 336.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.08 : 539.81 = 243.63 : x
  2. Step 2: Convert to fraction form
    391.08/539.81 = 243.63/x
  3. Step 3: Cross multiply
    391.08x = 539.81 × 243.63
  4. Step 4: Simplify right side
    391.08x = 131,512.69
  5. Step 5: Solve for x
    x = 131,512.69/391.08
  6. Step 6: Final answer
    x = 336.28

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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.