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Finding the Fourth Proportional to 203.79, 281.30 and 138.39

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Solution

The fourth proportional to 203.79, 281.30 and 138.39 is: 191.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    203.79 : 281.30 = 138.39 : x
  2. Step 2: Convert to fraction form
    203.79/281.30 = 138.39/x
  3. Step 3: Cross multiply
    203.79x = 281.30 × 138.39
  4. Step 4: Simplify right side
    203.79x = 38,928.42
  5. Step 5: Solve for x
    x = 38,928.42/203.79
  6. Step 6: Final answer
    x = 191.02

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.