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Finding the Fourth Proportional to 137.91, 190.32 and 79.70

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Solution

The fourth proportional to 137.91, 190.32 and 79.70 is: 109.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.91 : 190.32 = 79.70 : x
  2. Step 2: Convert to fraction form
    137.91/190.32 = 79.70/x
  3. Step 3: Cross multiply
    137.91x = 190.32 × 79.70
  4. Step 4: Simplify right side
    137.91x = 15,167.55
  5. Step 5: Solve for x
    x = 15,167.55/137.91
  6. Step 6: Final answer
    x = 109.98

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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.