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Finding the Fourth Proportional to 80.84, 121.04 and 68.64

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Solution

The fourth proportional to 80.84, 121.04 and 68.64 is: 102.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.84 : 121.04 = 68.64 : x
  2. Step 2: Convert to fraction form
    80.84/121.04 = 68.64/x
  3. Step 3: Cross multiply
    80.84x = 121.04 × 68.64
  4. Step 4: Simplify right side
    80.84x = 8,307.99
  5. Step 5: Solve for x
    x = 8,307.99/80.84
  6. Step 6: Final answer
    x = 102.77

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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.