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Finding the Third Proportional to 1.20 and 2.80

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Solution

The third proportional to 1.20 and 2.80 is: 6.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    1.20 : 2.80 = 2.80 : x
  2. Step 2: Convert to fraction form
    1.20/2.80 = 2.80/x
  3. Step 3: Cross multiply
    1.20x = 2.80 × 2.80
  4. Step 4: Simplify right side
    1.20x = 7.86
  5. Step 5: Solve for x
    x = 7.86/1.20
  6. Step 6: Final answer
    x = 6.54

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Why These Related Problems?

These problems maintain the same ratio (2.33) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.