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Finding the Fourth Proportional to 10.31, 14.21 and 8.13

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Solution

The fourth proportional to 10.31, 14.21 and 8.13 is: 11.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    10.31 : 14.21 = 8.13 : x
  2. Step 2: Convert to fraction form
    10.31/14.21 = 8.13/x
  3. Step 3: Cross multiply
    10.31x = 14.21 × 8.13
  4. Step 4: Simplify right side
    10.31x = 115.53
  5. Step 5: Solve for x
    x = 115.53/10.31
  6. Step 6: Final answer
    x = 11.21

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.