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Finding the Fourth Proportional to 99.81, 149.94 and 80.58

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Solution

The fourth proportional to 99.81, 149.94 and 80.58 is: 121.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    99.81 : 149.94 = 80.58 : x
  2. Step 2: Convert to fraction form
    99.81/149.94 = 80.58/x
  3. Step 3: Cross multiply
    99.81x = 149.94 × 80.58
  4. Step 4: Simplify right side
    99.81x = 12,082.17
  5. Step 5: Solve for x
    x = 12,082.17/99.81
  6. Step 6: Final answer
    x = 121.05

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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.