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Finding the Fourth Proportional to 215.39, 323.18 and 87.23

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Solution

The fourth proportional to 215.39, 323.18 and 87.23 is: 130.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    215.39 : 323.18 = 87.23 : x
  2. Step 2: Convert to fraction form
    215.39/323.18 = 87.23/x
  3. Step 3: Cross multiply
    215.39x = 323.18 × 87.23
  4. Step 4: Simplify right side
    215.39x = 28,191.69
  5. Step 5: Solve for x
    x = 28,191.69/215.39
  6. Step 6: Final answer
    x = 130.89

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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.