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Finding the Fourth Proportional to 379.40, 523.38 and 321.80

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Solution

The fourth proportional to 379.40, 523.38 and 321.80 is: 443.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    379.40 : 523.38 = 321.80 : x
  2. Step 2: Convert to fraction form
    379.40/523.38 = 321.80/x
  3. Step 3: Cross multiply
    379.40x = 523.38 × 321.80
  4. Step 4: Simplify right side
    379.40x = 168,423.68
  5. Step 5: Solve for x
    x = 168,423.68/379.40
  6. Step 6: Final answer
    x = 443.92

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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.