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Finding the Fourth Proportional to 137.20, 205.78 and 65.08

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Solution

The fourth proportional to 137.20, 205.78 and 65.08 is: 97.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.20 : 205.78 = 65.08 : x
  2. Step 2: Convert to fraction form
    137.20/205.78 = 65.08/x
  3. Step 3: Cross multiply
    137.20x = 205.78 × 65.08
  4. Step 4: Simplify right side
    137.20x = 13,392.16
  5. Step 5: Solve for x
    x = 13,392.16/137.20
  6. Step 6: Final answer
    x = 97.61

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.