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Finding the Fourth Proportional to 136.89, 205.35 and 72.75

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Solution

The fourth proportional to 136.89, 205.35 and 72.75 is: 109.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    136.89 : 205.35 = 72.75 : x
  2. Step 2: Convert to fraction form
    136.89/205.35 = 72.75/x
  3. Step 3: Cross multiply
    136.89x = 205.35 × 72.75
  4. Step 4: Simplify right side
    136.89x = 14,939.21
  5. Step 5: Solve for x
    x = 14,939.21/136.89
  6. Step 6: Final answer
    x = 109.13

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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.