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Finding the Fourth Proportional to 135.81, 203.72 and 90.18

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Solution

The fourth proportional to 135.81, 203.72 and 90.18 is: 135.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    135.81 : 203.72 = 90.18 : x
  2. Step 2: Convert to fraction form
    135.81/203.72 = 90.18/x
  3. Step 3: Cross multiply
    135.81x = 203.72 × 90.18
  4. Step 4: Simplify right side
    135.81x = 18,371.02
  5. Step 5: Solve for x
    x = 18,371.02/135.81
  6. Step 6: Final answer
    x = 135.27

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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.