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Finding the Fourth Proportional to 205.50, 308.25 and 91.50

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Solution

The fourth proportional to 205.50, 308.25 and 91.50 is: 137.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.50 : 308.25 = 91.50 : x
  2. Step 2: Convert to fraction form
    205.50/308.25 = 91.50/x
  3. Step 3: Cross multiply
    205.50x = 308.25 × 91.50
  4. Step 4: Simplify right side
    205.50x = 28,204.88
  5. Step 5: Solve for x
    x = 28,204.88/205.50
  6. Step 6: Final answer
    x = 137.25

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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.