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Finding the Fourth Proportional to 305.91, 421.77 and 239.39

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Solution

The fourth proportional to 305.91, 421.77 and 239.39 is: 330.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.91 : 421.77 = 239.39 : x
  2. Step 2: Convert to fraction form
    305.91/421.77 = 239.39/x
  3. Step 3: Cross multiply
    305.91x = 421.77 × 239.39
  4. Step 4: Simplify right side
    305.91x = 100,967.52
  5. Step 5: Solve for x
    x = 100,967.52/305.91
  6. Step 6: Final answer
    x = 330.06

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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.