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Finding the Fourth Proportional to 339.33, 511.31 and 279.80

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Solution

The fourth proportional to 339.33, 511.31 and 279.80 is: 421.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    339.33 : 511.31 = 279.80 : x
  2. Step 2: Convert to fraction form
    339.33/511.31 = 279.80/x
  3. Step 3: Cross multiply
    339.33x = 511.31 × 279.80
  4. Step 4: Simplify right side
    339.33x = 143,064.54
  5. Step 5: Solve for x
    x = 143,064.54/339.33
  6. Step 6: Final answer
    x = 421.61

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.