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Finding the Fourth Proportional to 90.15, 134.65 and 80.49

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Solution

The fourth proportional to 90.15, 134.65 and 80.49 is: 120.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.15 : 134.65 = 80.49 : x
  2. Step 2: Convert to fraction form
    90.15/134.65 = 80.49/x
  3. Step 3: Cross multiply
    90.15x = 134.65 × 80.49
  4. Step 4: Simplify right side
    90.15x = 10,837.98
  5. Step 5: Solve for x
    x = 10,837.98/90.15
  6. Step 6: Final answer
    x = 120.22

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.