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Finding the Fourth Proportional to 137.80, 205.73 and 125.80

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Solution

The fourth proportional to 137.80, 205.73 and 125.80 is: 187.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.80 : 205.73 = 125.80 : x
  2. Step 2: Convert to fraction form
    137.80/205.73 = 125.80/x
  3. Step 3: Cross multiply
    137.80x = 205.73 × 125.80
  4. Step 4: Simplify right side
    137.80x = 25,880.83
  5. Step 5: Solve for x
    x = 25,880.83/137.80
  6. Step 6: Final answer
    x = 187.81

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.