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Finding the Fourth Proportional to 391.30, 586.74 and 185.80

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Solution

The fourth proportional to 391.30, 586.74 and 185.80 is: 278.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.30 : 586.74 = 185.80 : x
  2. Step 2: Convert to fraction form
    391.30/586.74 = 185.80/x
  3. Step 3: Cross multiply
    391.30x = 586.74 × 185.80
  4. Step 4: Simplify right side
    391.30x = 109,016.29
  5. Step 5: Solve for x
    x = 109,016.29/391.30
  6. Step 6: Final answer
    x = 278.60

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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.