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Finding the Fourth Proportional to 311.71, 429.88 and 256.12

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Solution

The fourth proportional to 311.71, 429.88 and 256.12 is: 353.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    311.71 : 429.88 = 256.12 : x
  2. Step 2: Convert to fraction form
    311.71/429.88 = 256.12/x
  3. Step 3: Cross multiply
    311.71x = 429.88 × 256.12
  4. Step 4: Simplify right side
    311.71x = 110,100.87
  5. Step 5: Solve for x
    x = 110,100.87/311.71
  6. Step 6: Final answer
    x = 353.22

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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.