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Finding the Fourth Proportional to 80.63, 121.04 and 69.87

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Solution

The fourth proportional to 80.63, 121.04 and 69.87 is: 104.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.63 : 121.04 = 69.87 : x
  2. Step 2: Convert to fraction form
    80.63/121.04 = 69.87/x
  3. Step 3: Cross multiply
    80.63x = 121.04 × 69.87
  4. Step 4: Simplify right side
    80.63x = 8,457.06
  5. Step 5: Solve for x
    x = 8,457.06/80.63
  6. Step 6: Final answer
    x = 104.89

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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.