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Finding the Fourth Proportional to 138.52, 191.28 and 89.47

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Solution

The fourth proportional to 138.52, 191.28 and 89.47 is: 123.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.52 : 191.28 = 89.47 : x
  2. Step 2: Convert to fraction form
    138.52/191.28 = 89.47/x
  3. Step 3: Cross multiply
    138.52x = 191.28 × 89.47
  4. Step 4: Simplify right side
    138.52x = 17,113.82
  5. Step 5: Solve for x
    x = 17,113.82/138.52
  6. Step 6: Final answer
    x = 123.55

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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.