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Finding the Fourth Proportional to 305.11, 421.03 and 187.03

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Solution

The fourth proportional to 305.11, 421.03 and 187.03 is: 258.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.11 : 421.03 = 187.03 : x
  2. Step 2: Convert to fraction form
    305.11/421.03 = 187.03/x
  3. Step 3: Cross multiply
    305.11x = 421.03 × 187.03
  4. Step 4: Simplify right side
    305.11x = 78,744.95
  5. Step 5: Solve for x
    x = 78,744.95/305.11
  6. Step 6: Final answer
    x = 258.09

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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.