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Finding the Fourth Proportional to 123.20, 170.12 and 98.75

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Solution

The fourth proportional to 123.20, 170.12 and 98.75 is: 136.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    123.20 : 170.12 = 98.75 : x
  2. Step 2: Convert to fraction form
    123.20/170.12 = 98.75/x
  3. Step 3: Cross multiply
    123.20x = 170.12 × 98.75
  4. Step 4: Simplify right side
    123.20x = 16,799.35
  5. Step 5: Solve for x
    x = 16,799.35/123.20
  6. Step 6: Final answer
    x = 136.36

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.