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Finding the Fourth Proportional to 91.06, 136.38 and 90.39

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Solution

The fourth proportional to 91.06, 136.38 and 90.39 is: 135.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    91.06 : 136.38 = 90.39 : x
  2. Step 2: Convert to fraction form
    91.06/136.38 = 90.39/x
  3. Step 3: Cross multiply
    91.06x = 136.38 × 90.39
  4. Step 4: Simplify right side
    91.06x = 12,327.39
  5. Step 5: Solve for x
    x = 12,327.39/91.06
  6. Step 6: Final answer
    x = 135.38

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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.