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Finding the Third Proportional to 78 and 83

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Solution

The third proportional to 78 and 83 is: 88.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    78 : 83 = 83 : x
  2. Step 2: Convert to fraction form
    78/83 = 83/x
  3. Step 3: Cross multiply
    78x = 83 × 83
  4. Step 4: Simplify right side
    78x = 6,889
  5. Step 5: Solve for x
    x = 6,889/78
  6. Step 6: Final answer
    x = 88.32

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Why These Related Problems?

These problems maintain the same ratio (1.06) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.