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Finding the Fourth Proportional to 137.99, 190.42 and 79.78

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Solution

The fourth proportional to 137.99, 190.42 and 79.78 is: 110.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.99 : 190.42 = 79.78 : x
  2. Step 2: Convert to fraction form
    137.99/190.42 = 79.78/x
  3. Step 3: Cross multiply
    137.99x = 190.42 × 79.78
  4. Step 4: Simplify right side
    137.99x = 15,191.71
  5. Step 5: Solve for x
    x = 15,191.71/137.99
  6. Step 6: Final answer
    x = 110.09

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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.