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Finding the Fourth Proportional to 101.25, 138.78 and 98.62

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Solution

The fourth proportional to 101.25, 138.78 and 98.62 is: 135.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.25 : 138.78 = 98.62 : x
  2. Step 2: Convert to fraction form
    101.25/138.78 = 98.62/x
  3. Step 3: Cross multiply
    101.25x = 138.78 × 98.62
  4. Step 4: Simplify right side
    101.25x = 13,686.14
  5. Step 5: Solve for x
    x = 13,686.14/101.25
  6. Step 6: Final answer
    x = 135.17

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.