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Finding the Fourth Proportional to 208.15, 312.23 and 54.09

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Solution

The fourth proportional to 208.15, 312.23 and 54.09 is: 81.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.15 : 312.23 = 54.09 : x
  2. Step 2: Convert to fraction form
    208.15/312.23 = 54.09/x
  3. Step 3: Cross multiply
    208.15x = 312.23 × 54.09
  4. Step 4: Simplify right side
    208.15x = 16,888.66
  5. Step 5: Solve for x
    x = 16,888.66/208.15
  6. Step 6: Final answer
    x = 81.14

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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.