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Finding the Third Proportional to 11.53 and 21.40

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Solution

The third proportional to 11.53 and 21.40 is: 39.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    11.53 : 21.40 = 21.40 : x
  2. Step 2: Convert to fraction form
    11.53/21.40 = 21.40/x
  3. Step 3: Cross multiply
    11.53x = 21.40 × 21.40
  4. Step 4: Simplify right side
    11.53x = 458.05
  5. Step 5: Solve for x
    x = 458.05/11.53
  6. Step 6: Final answer
    x = 39.72

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Why These Related Problems?

These problems maintain the same ratio (1.86) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.