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Finding the Fourth Proportional to 311.30, 429.72 and 200.78

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Solution

The fourth proportional to 311.30, 429.72 and 200.78 is: 277.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    311.30 : 429.72 = 200.78 : x
  2. Step 2: Convert to fraction form
    311.30/429.72 = 200.78/x
  3. Step 3: Cross multiply
    311.30x = 429.72 × 200.78
  4. Step 4: Simplify right side
    311.30x = 86,279.18
  5. Step 5: Solve for x
    x = 86,279.18/311.30
  6. Step 6: Final answer
    x = 277.16

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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.