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Finding the Fourth Proportional to 208.07, 312.09 and 79.82

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Solution

The fourth proportional to 208.07, 312.09 and 79.82 is: 119.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.07 : 312.09 = 79.82 : x
  2. Step 2: Convert to fraction form
    208.07/312.09 = 79.82/x
  3. Step 3: Cross multiply
    208.07x = 312.09 × 79.82
  4. Step 4: Simplify right side
    208.07x = 24,911.02
  5. Step 5: Solve for x
    x = 24,911.02/208.07
  6. Step 6: Final answer
    x = 119.72

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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.