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Finding the Third Proportional to 39 and 39.75

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Solution

The third proportional to 39 and 39.75 is: 40.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    39 : 39.75 = 39.75 : x
  2. Step 2: Convert to fraction form
    39/39.75 = 39.75/x
  3. Step 3: Cross multiply
    39x = 39.75 × 39.75
  4. Step 4: Simplify right side
    39x = 1,580.06
  5. Step 5: Solve for x
    x = 1,580.06/39
  6. Step 6: Final answer
    x = 40.51

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Why These Related Problems?

These problems maintain the same ratio (1.02) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.