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Finding the Fourth Proportional to 305.30, 421.26 and 180.90

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Solution

The fourth proportional to 305.30, 421.26 and 180.90 is: 249.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.30 : 421.26 = 180.90 : x
  2. Step 2: Convert to fraction form
    305.30/421.26 = 180.90/x
  3. Step 3: Cross multiply
    305.30x = 421.26 × 180.90
  4. Step 4: Simplify right side
    305.30x = 76,205.93
  5. Step 5: Solve for x
    x = 76,205.93/305.30
  6. Step 6: Final answer
    x = 249.61

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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.