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Finding the Fourth Proportional to 13.20, 19.79 and 7.17

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Solution

The fourth proportional to 13.20, 19.79 and 7.17 is: 10.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    13.20 : 19.79 = 7.17 : x
  2. Step 2: Convert to fraction form
    13.20/19.79 = 7.17/x
  3. Step 3: Cross multiply
    13.20x = 19.79 × 7.17
  4. Step 4: Simplify right side
    13.20x = 141.96
  5. Step 5: Solve for x
    x = 141.96/13.20
  6. Step 6: Final answer
    x = 10.76

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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.