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Finding the Fourth Proportional to 10.04, 13.80 and 8.21

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Solution

The fourth proportional to 10.04, 13.80 and 8.21 is: 11.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    10.04 : 13.80 = 8.21 : x
  2. Step 2: Convert to fraction form
    10.04/13.80 = 8.21/x
  3. Step 3: Cross multiply
    10.04x = 13.80 × 8.21
  4. Step 4: Simplify right side
    10.04x = 113.30
  5. Step 5: Solve for x
    x = 113.30/10.04
  6. Step 6: Final answer
    x = 11.28

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.