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Finding the Fourth Proportional to 305.29, 421.28 and 187.29

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Solution

The fourth proportional to 305.29, 421.28 and 187.29 is: 258.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.29 : 421.28 = 187.29 : x
  2. Step 2: Convert to fraction form
    305.29/421.28 = 187.29/x
  3. Step 3: Cross multiply
    305.29x = 421.28 × 187.29
  4. Step 4: Simplify right side
    305.29x = 78,899.59
  5. Step 5: Solve for x
    x = 78,899.59/305.29
  6. Step 6: Final answer
    x = 258.44

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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.