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Finding the Fourth Proportional to 208.92, 312.58 and 127.81

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Solution

The fourth proportional to 208.92, 312.58 and 127.81 is: 191.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.92 : 312.58 = 127.81 : x
  2. Step 2: Convert to fraction form
    208.92/312.58 = 127.81/x
  3. Step 3: Cross multiply
    208.92x = 312.58 × 127.81
  4. Step 4: Simplify right side
    208.92x = 39,950.85
  5. Step 5: Solve for x
    x = 39,950.85/208.92
  6. Step 6: Final answer
    x = 191.23

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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.