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Finding the Third Proportional to 5 and 8

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Solution

The third proportional to 5 and 8 is: 12.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    5 : 8 = 8 : x
  2. Step 2: Convert to fraction form
    5/8 = 8/x
  3. Step 3: Cross multiply
    5x = 8 × 8
  4. Step 4: Simplify right side
    5x = 64
  5. Step 5: Solve for x
    x = 64/5
  6. Step 6: Final answer
    x = 12.80

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Why These Related Problems?

These problems maintain the same ratio (1.60) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.