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Finding the Fourth Proportional to 391.30, 540.06 and 297.90

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Solution

The fourth proportional to 391.30, 540.06 and 297.90 is: 411.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.30 : 540.06 = 297.90 : x
  2. Step 2: Convert to fraction form
    391.30/540.06 = 297.90/x
  3. Step 3: Cross multiply
    391.30x = 540.06 × 297.90
  4. Step 4: Simplify right side
    391.30x = 160,881.17
  5. Step 5: Solve for x
    x = 160,881.17/391.30
  6. Step 6: Final answer
    x = 411.15

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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.