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Finding the Fourth Proportional to 200.09, 300.31 and 90.38

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Solution

The fourth proportional to 200.09, 300.31 and 90.38 is: 135.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    200.09 : 300.31 = 90.38 : x
  2. Step 2: Convert to fraction form
    200.09/300.31 = 90.38/x
  3. Step 3: Cross multiply
    200.09x = 300.31 × 90.38
  4. Step 4: Simplify right side
    200.09x = 27,142.54
  5. Step 5: Solve for x
    x = 27,142.54/200.09
  6. Step 6: Final answer
    x = 135.65

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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.