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Finding the Fourth Proportional to 208.20, 312.29 and 63.91

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Solution

The fourth proportional to 208.20, 312.29 and 63.91 is: 95.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.20 : 312.29 = 63.91 : x
  2. Step 2: Convert to fraction form
    208.20/312.29 = 63.91/x
  3. Step 3: Cross multiply
    208.20x = 312.29 × 63.91
  4. Step 4: Simplify right side
    208.20x = 19,959.91
  5. Step 5: Solve for x
    x = 19,959.91/208.20
  6. Step 6: Final answer
    x = 95.87

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.