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Finding the Fourth Proportional to 10.20, 14.09 and 7.79

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Solution

The fourth proportional to 10.20, 14.09 and 7.79 is: 10.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    10.20 : 14.09 = 7.79 : x
  2. Step 2: Convert to fraction form
    10.20/14.09 = 7.79/x
  3. Step 3: Cross multiply
    10.20x = 14.09 × 7.79
  4. Step 4: Simplify right side
    10.20x = 109.76
  5. Step 5: Solve for x
    x = 109.76/10.20
  6. Step 6: Final answer
    x = 10.76

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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.