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Finding the Fourth Proportional to 8.04, 12.20 and 7.80

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Solution

The fourth proportional to 8.04, 12.20 and 7.80 is: 11.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    8.04 : 12.20 = 7.80 : x
  2. Step 2: Convert to fraction form
    8.04/12.20 = 7.80/x
  3. Step 3: Cross multiply
    8.04x = 12.20 × 7.80
  4. Step 4: Simplify right side
    8.04x = 95.16
  5. Step 5: Solve for x
    x = 95.16/8.04
  6. Step 6: Final answer
    x = 11.84

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Why These Related Problems?

These problems maintain the same ratio (1.52) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.