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Finding the Fourth Proportional to 321.08, 480.80 and 279.76

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Solution

The fourth proportional to 321.08, 480.80 and 279.76 is: 418.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    321.08 : 480.80 = 279.76 : x
  2. Step 2: Convert to fraction form
    321.08/480.80 = 279.76/x
  3. Step 3: Cross multiply
    321.08x = 480.80 × 279.76
  4. Step 4: Simplify right side
    321.08x = 134,508.61
  5. Step 5: Solve for x
    x = 134,508.61/321.08
  6. Step 6: Final answer
    x = 418.93

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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.