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Finding the Fourth Proportional to 137.19, 189.32 and 78.97

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Solution

The fourth proportional to 137.19, 189.32 and 78.97 is: 108.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.19 : 189.32 = 78.97 : x
  2. Step 2: Convert to fraction form
    137.19/189.32 = 78.97/x
  3. Step 3: Cross multiply
    137.19x = 189.32 × 78.97
  4. Step 4: Simplify right side
    137.19x = 14,950.60
  5. Step 5: Solve for x
    x = 14,950.60/137.19
  6. Step 6: Final answer
    x = 108.98

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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.