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Finding the Third Proportional to 7.87 and 15.74

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Solution

The third proportional to 7.87 and 15.74 is: 31.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    7.87 : 15.74 = 15.74 : x
  2. Step 2: Convert to fraction form
    7.87/15.74 = 15.74/x
  3. Step 3: Cross multiply
    7.87x = 15.74 × 15.74
  4. Step 4: Simplify right side
    7.87x = 247.60
  5. Step 5: Solve for x
    x = 247.60/7.87
  6. Step 6: Final answer
    x = 31.47

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Why These Related Problems?

These problems maintain the same ratio (2.00) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.