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Finding the Fourth Proportional to 80.65, 121.29 and 68.53

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Solution

The fourth proportional to 80.65, 121.29 and 68.53 is: 103.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.65 : 121.29 = 68.53 : x
  2. Step 2: Convert to fraction form
    80.65/121.29 = 68.53/x
  3. Step 3: Cross multiply
    80.65x = 121.29 × 68.53
  4. Step 4: Simplify right side
    80.65x = 8,312.00
  5. Step 5: Solve for x
    x = 8,312.00/80.65
  6. Step 6: Final answer
    x = 103.06

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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.