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Finding the Fourth Proportional to 84.99, 126.81 and 76.89

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Solution

The fourth proportional to 84.99, 126.81 and 76.89 is: 114.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    84.99 : 126.81 = 76.89 : x
  2. Step 2: Convert to fraction form
    84.99/126.81 = 76.89/x
  3. Step 3: Cross multiply
    84.99x = 126.81 × 76.89
  4. Step 4: Simplify right side
    84.99x = 9,750.42
  5. Step 5: Solve for x
    x = 9,750.42/84.99
  6. Step 6: Final answer
    x = 114.72

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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.