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Finding the Fourth Proportional to 391.02, 586.05 and 217.68

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Solution

The fourth proportional to 391.02, 586.05 and 217.68 is: 326.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.02 : 586.05 = 217.68 : x
  2. Step 2: Convert to fraction form
    391.02/586.05 = 217.68/x
  3. Step 3: Cross multiply
    391.02x = 586.05 × 217.68
  4. Step 4: Simplify right side
    391.02x = 127,571.36
  5. Step 5: Solve for x
    x = 127,571.36/391.02
  6. Step 6: Final answer
    x = 326.25

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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.