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Finding the Fourth Proportional to 10.15, 15.21 and 8.14

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Solution

The fourth proportional to 10.15, 15.21 and 8.14 is: 12.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    10.15 : 15.21 = 8.14 : x
  2. Step 2: Convert to fraction form
    10.15/15.21 = 8.14/x
  3. Step 3: Cross multiply
    10.15x = 15.21 × 8.14
  4. Step 4: Simplify right side
    10.15x = 123.81
  5. Step 5: Solve for x
    x = 123.81/10.15
  6. Step 6: Final answer
    x = 12.20

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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.