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Finding the Fourth Proportional to 391.49, 540.43 and 342.89

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Solution

The fourth proportional to 391.49, 540.43 and 342.89 is: 473.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.49 : 540.43 = 342.89 : x
  2. Step 2: Convert to fraction form
    391.49/540.43 = 342.89/x
  3. Step 3: Cross multiply
    391.49x = 540.43 × 342.89
  4. Step 4: Simplify right side
    391.49x = 185,304.48
  5. Step 5: Solve for x
    x = 185,304.48/391.49
  6. Step 6: Final answer
    x = 473.34

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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.