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Finding the Third Proportional to 10.50 and 20

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Solution

The third proportional to 10.50 and 20 is: 38.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    10.50 : 20 = 20 : x
  2. Step 2: Convert to fraction form
    10.50/20 = 20/x
  3. Step 3: Cross multiply
    10.50x = 20 × 20
  4. Step 4: Simplify right side
    10.50x = 400
  5. Step 5: Solve for x
    x = 400/10.50
  6. Step 6: Final answer
    x = 38.10

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Why These Related Problems?

These problems maintain the same ratio (1.90) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.