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Finding the Fourth Proportional to 87.90, 121.26 and 73.38

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Solution

The fourth proportional to 87.90, 121.26 and 73.38 is: 101.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.90 : 121.26 = 73.38 : x
  2. Step 2: Convert to fraction form
    87.90/121.26 = 73.38/x
  3. Step 3: Cross multiply
    87.90x = 121.26 × 73.38
  4. Step 4: Simplify right side
    87.90x = 8,898.06
  5. Step 5: Solve for x
    x = 8,898.06/87.90
  6. Step 6: Final answer
    x = 101.23

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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.