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Finding the Third Proportional to 90 and 102.50

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Solution

The third proportional to 90 and 102.50 is: 116.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    90 : 102.50 = 102.50 : x
  2. Step 2: Convert to fraction form
    90/102.50 = 102.50/x
  3. Step 3: Cross multiply
    90x = 102.50 × 102.50
  4. Step 4: Simplify right side
    90x = 10,506.25
  5. Step 5: Solve for x
    x = 10,506.25/90
  6. Step 6: Final answer
    x = 116.74

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Why These Related Problems?

These problems maintain the same ratio (1.14) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.