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Finding the Fourth Proportional to 137.70, 190.15 and 105.20

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Solution

The fourth proportional to 137.70, 190.15 and 105.20 is: 145.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.70 : 190.15 = 105.20 : x
  2. Step 2: Convert to fraction form
    137.70/190.15 = 105.20/x
  3. Step 3: Cross multiply
    137.70x = 190.15 × 105.20
  4. Step 4: Simplify right side
    137.70x = 20,003.28
  5. Step 5: Solve for x
    x = 20,003.28/137.70
  6. Step 6: Final answer
    x = 145.27

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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.