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Finding the Fourth Proportional to 311.35, 429.85 and 187.05

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Solution

The fourth proportional to 311.35, 429.85 and 187.05 is: 258.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    311.35 : 429.85 = 187.05 : x
  2. Step 2: Convert to fraction form
    311.35/429.85 = 187.05/x
  3. Step 3: Cross multiply
    311.35x = 429.85 × 187.05
  4. Step 4: Simplify right side
    311.35x = 80,403.44
  5. Step 5: Solve for x
    x = 80,403.44/311.35
  6. Step 6: Final answer
    x = 258.24

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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.