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Finding the Fourth Proportional to 319.80, 479.82 and 217.20

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Solution

The fourth proportional to 319.80, 479.82 and 217.20 is: 325.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.80 : 479.82 = 217.20 : x
  2. Step 2: Convert to fraction form
    319.80/479.82 = 217.20/x
  3. Step 3: Cross multiply
    319.80x = 479.82 × 217.20
  4. Step 4: Simplify right side
    319.80x = 104,216.90
  5. Step 5: Solve for x
    x = 104,216.90/319.80
  6. Step 6: Final answer
    x = 325.88

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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.