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Finding the Fourth Proportional to 208.29, 312.47 and 102.79

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Solution

The fourth proportional to 208.29, 312.47 and 102.79 is: 154.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.29 : 312.47 = 102.79 : x
  2. Step 2: Convert to fraction form
    208.29/312.47 = 102.79/x
  3. Step 3: Cross multiply
    208.29x = 312.47 × 102.79
  4. Step 4: Simplify right side
    208.29x = 32,118.79
  5. Step 5: Solve for x
    x = 32,118.79/208.29
  6. Step 6: Final answer
    x = 154.20

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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.