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Finding the Fourth Proportional to 138.52, 191.08 and 89.39

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Solution

The fourth proportional to 138.52, 191.08 and 89.39 is: 123.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.52 : 191.08 = 89.39 : x
  2. Step 2: Convert to fraction form
    138.52/191.08 = 89.39/x
  3. Step 3: Cross multiply
    138.52x = 191.08 × 89.39
  4. Step 4: Simplify right side
    138.52x = 17,080.41
  5. Step 5: Solve for x
    x = 17,080.41/138.52
  6. Step 6: Final answer
    x = 123.31

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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.