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Finding the Third Proportional to 4.31 and 8.91

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Solution

The third proportional to 4.31 and 8.91 is: 18.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    4.31 : 8.91 = 8.91 : x
  2. Step 2: Convert to fraction form
    4.31/8.91 = 8.91/x
  3. Step 3: Cross multiply
    4.31x = 8.91 × 8.91
  4. Step 4: Simplify right side
    4.31x = 79.32
  5. Step 5: Solve for x
    x = 79.32/4.31
  6. Step 6: Final answer
    x = 18.39

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Why These Related Problems?

These problems maintain the same ratio (2.07) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.