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Finding the Fourth Proportional to 137.54, 189.81 and 79.31

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Solution

The fourth proportional to 137.54, 189.81 and 79.31 is: 109.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.54 : 189.81 = 79.31 : x
  2. Step 2: Convert to fraction form
    137.54/189.81 = 79.31/x
  3. Step 3: Cross multiply
    137.54x = 189.81 × 79.31
  4. Step 4: Simplify right side
    137.54x = 15,054.31
  5. Step 5: Solve for x
    x = 15,054.31/137.54
  6. Step 6: Final answer
    x = 109.45

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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.