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Finding the Fourth Proportional to 208.19, 287.31 and 119.65

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Solution

The fourth proportional to 208.19, 287.31 and 119.65 is: 165.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.19 : 287.31 = 119.65 : x
  2. Step 2: Convert to fraction form
    208.19/287.31 = 119.65/x
  3. Step 3: Cross multiply
    208.19x = 287.31 × 119.65
  4. Step 4: Simplify right side
    208.19x = 34,376.04
  5. Step 5: Solve for x
    x = 34,376.04/208.19
  6. Step 6: Final answer
    x = 165.12

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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.