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Finding the Fourth Proportional to 391.65, 587.49 and 218.22

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Solution

The fourth proportional to 391.65, 587.49 and 218.22 is: 327.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.65 : 587.49 = 218.22 : x
  2. Step 2: Convert to fraction form
    391.65/587.49 = 218.22/x
  3. Step 3: Cross multiply
    391.65x = 587.49 × 218.22
  4. Step 4: Simplify right side
    391.65x = 128,200.98
  5. Step 5: Solve for x
    x = 128,200.98/391.65
  6. Step 6: Final answer
    x = 327.34

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.