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Finding the Fourth Proportional to 137.84, 205.77 and 128.74

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Solution

The fourth proportional to 137.84, 205.77 and 128.74 is: 192.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.84 : 205.77 = 128.74 : x
  2. Step 2: Convert to fraction form
    137.84/205.77 = 128.74/x
  3. Step 3: Cross multiply
    137.84x = 205.77 × 128.74
  4. Step 4: Simplify right side
    137.84x = 26,490.83
  5. Step 5: Solve for x
    x = 26,490.83/137.84
  6. Step 6: Final answer
    x = 192.19

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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.