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Finding the Third Proportional to 3.45 and 6.90

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Solution

The third proportional to 3.45 and 6.90 is: 13.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.45 : 6.90 = 6.90 : x
  2. Step 2: Convert to fraction form
    3.45/6.90 = 6.90/x
  3. Step 3: Cross multiply
    3.45x = 6.90 × 6.90
  4. Step 4: Simplify right side
    3.45x = 47.60
  5. Step 5: Solve for x
    x = 47.60/3.45
  6. Step 6: Final answer
    x = 13.80

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1.5x scale

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.