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Finding the Fourth Proportional to 90.23, 135.49 and 81.41

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Solution

The fourth proportional to 90.23, 135.49 and 81.41 is: 122.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.23 : 135.49 = 81.41 : x
  2. Step 2: Convert to fraction form
    90.23/135.49 = 81.41/x
  3. Step 3: Cross multiply
    90.23x = 135.49 × 81.41
  4. Step 4: Simplify right side
    90.23x = 11,030.38
  5. Step 5: Solve for x
    x = 11,030.38/90.23
  6. Step 6: Final answer
    x = 122.25

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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.