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Finding the Fourth Proportional to 208.17, 287.28 and 138.11

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Solution

The fourth proportional to 208.17, 287.28 and 138.11 is: 190.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.17 : 287.28 = 138.11 : x
  2. Step 2: Convert to fraction form
    208.17/287.28 = 138.11/x
  3. Step 3: Cross multiply
    208.17x = 287.28 × 138.11
  4. Step 4: Simplify right side
    208.17x = 39,674.80
  5. Step 5: Solve for x
    x = 39,674.80/208.17
  6. Step 6: Final answer
    x = 190.59

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.