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Finding the Fourth Proportional to 138.51, 207.62 and 89.75

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Solution

The fourth proportional to 138.51, 207.62 and 89.75 is: 134.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.51 : 207.62 = 89.75 : x
  2. Step 2: Convert to fraction form
    138.51/207.62 = 89.75/x
  3. Step 3: Cross multiply
    138.51x = 207.62 × 89.75
  4. Step 4: Simplify right side
    138.51x = 18,633.90
  5. Step 5: Solve for x
    x = 18,633.90/138.51
  6. Step 6: Final answer
    x = 134.53

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.