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Finding the Fourth Proportional to 90.19, 135.01 and 69.81

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Solution

The fourth proportional to 90.19, 135.01 and 69.81 is: 104.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.19 : 135.01 = 69.81 : x
  2. Step 2: Convert to fraction form
    90.19/135.01 = 69.81/x
  3. Step 3: Cross multiply
    90.19x = 135.01 × 69.81
  4. Step 4: Simplify right side
    90.19x = 9,425.05
  5. Step 5: Solve for x
    x = 9,425.05/90.19
  6. Step 6: Final answer
    x = 104.50

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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.