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Finding the Fourth Proportional to 217.30, 299.80 and 138.62

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Solution

The fourth proportional to 217.30, 299.80 and 138.62 is: 191.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    217.30 : 299.80 = 138.62 : x
  2. Step 2: Convert to fraction form
    217.30/299.80 = 138.62/x
  3. Step 3: Cross multiply
    217.30x = 299.80 × 138.62
  4. Step 4: Simplify right side
    217.30x = 41,558.42
  5. Step 5: Solve for x
    x = 41,558.42/217.30
  6. Step 6: Final answer
    x = 191.25

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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.