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Finding the Third Proportional to 4.09 and 8.70

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Solution

The third proportional to 4.09 and 8.70 is: 18.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    4.09 : 8.70 = 8.70 : x
  2. Step 2: Convert to fraction form
    4.09/8.70 = 8.70/x
  3. Step 3: Cross multiply
    4.09x = 8.70 × 8.70
  4. Step 4: Simplify right side
    4.09x = 75.72
  5. Step 5: Solve for x
    x = 75.72/4.09
  6. Step 6: Final answer
    x = 18.53

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Why These Related Problems?

These problems maintain the same ratio (2.13) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.