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Finding the Fourth Proportional to 90.10, 134.54 and 77.11

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Solution

The fourth proportional to 90.10, 134.54 and 77.11 is: 115.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.10 : 134.54 = 77.11 : x
  2. Step 2: Convert to fraction form
    90.10/134.54 = 77.11/x
  3. Step 3: Cross multiply
    90.10x = 134.54 × 77.11
  4. Step 4: Simplify right side
    90.10x = 10,374.24
  5. Step 5: Solve for x
    x = 10,374.24/90.10
  6. Step 6: Final answer
    x = 115.14

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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.