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Finding the Fourth Proportional to 10.15, 13.90 and 9.81

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Solution

The fourth proportional to 10.15, 13.90 and 9.81 is: 13.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    10.15 : 13.90 = 9.81 : x
  2. Step 2: Convert to fraction form
    10.15/13.90 = 9.81/x
  3. Step 3: Cross multiply
    10.15x = 13.90 × 9.81
  4. Step 4: Simplify right side
    10.15x = 136.35
  5. Step 5: Solve for x
    x = 136.35/10.15
  6. Step 6: Final answer
    x = 13.44

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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.