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Finding the Fourth Proportional to 391.35, 540.02 and 225.55

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Solution

The fourth proportional to 391.35, 540.02 and 225.55 is: 311.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.35 : 540.02 = 225.55 : x
  2. Step 2: Convert to fraction form
    391.35/540.02 = 225.55/x
  3. Step 3: Cross multiply
    391.35x = 540.02 × 225.55
  4. Step 4: Simplify right side
    391.35x = 121,801.51
  5. Step 5: Solve for x
    x = 121,801.51/391.35
  6. Step 6: Final answer
    x = 311.23

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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.