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Finding the Fourth Proportional to 391.40, 586.02 and 254.60

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Solution

The fourth proportional to 391.40, 586.02 and 254.60 is: 381.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.40 : 586.02 = 254.60 : x
  2. Step 2: Convert to fraction form
    391.40/586.02 = 254.60/x
  3. Step 3: Cross multiply
    391.40x = 586.02 × 254.60
  4. Step 4: Simplify right side
    391.40x = 149,200.69
  5. Step 5: Solve for x
    x = 149,200.69/391.40
  6. Step 6: Final answer
    x = 381.20

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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.