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Finding the Fourth Proportional to 136.28, 204.21 and 90.71

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Solution

The fourth proportional to 136.28, 204.21 and 90.71 is: 135.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    136.28 : 204.21 = 90.71 : x
  2. Step 2: Convert to fraction form
    136.28/204.21 = 90.71/x
  3. Step 3: Cross multiply
    136.28x = 204.21 × 90.71
  4. Step 4: Simplify right side
    136.28x = 18,523.89
  5. Step 5: Solve for x
    x = 18,523.89/136.28
  6. Step 6: Final answer
    x = 135.93

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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.