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Finding the Fourth Proportional to 13.30, 19.89 and 11

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Solution

The fourth proportional to 13.30, 19.89 and 11 is: 16.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    13.30 : 19.89 = 11 : x
  2. Step 2: Convert to fraction form
    13.30/19.89 = 11/x
  3. Step 3: Cross multiply
    13.30x = 19.89 × 11
  4. Step 4: Simplify right side
    13.30x = 218.79
  5. Step 5: Solve for x
    x = 218.79/13.30
  6. Step 6: Final answer
    x = 16.45

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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.