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Finding the Third Proportional to 42 and 54

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Solution

The third proportional to 42 and 54 is: 69.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    42 : 54 = 54 : x
  2. Step 2: Convert to fraction form
    42/54 = 54/x
  3. Step 3: Cross multiply
    42x = 54 × 54
  4. Step 4: Simplify right side
    42x = 2,916
  5. Step 5: Solve for x
    x = 2,916/42
  6. Step 6: Final answer
    x = 69.43

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Why These Related Problems?

These problems maintain the same ratio (1.29) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.