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Finding the Fourth Proportional to 90.19, 123.86 and 75.61

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Solution

The fourth proportional to 90.19, 123.86 and 75.61 is: 103.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.19 : 123.86 = 75.61 : x
  2. Step 2: Convert to fraction form
    90.19/123.86 = 75.61/x
  3. Step 3: Cross multiply
    90.19x = 123.86 × 75.61
  4. Step 4: Simplify right side
    90.19x = 9,365.05
  5. Step 5: Solve for x
    x = 9,365.05/90.19
  6. Step 6: Final answer
    x = 103.84

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.