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Finding the Fourth Proportional to 215.18, 320.71 and 213.56

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Solution

The fourth proportional to 215.18, 320.71 and 213.56 is: 318.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    215.18 : 320.71 = 213.56 : x
  2. Step 2: Convert to fraction form
    215.18/320.71 = 213.56/x
  3. Step 3: Cross multiply
    215.18x = 320.71 × 213.56
  4. Step 4: Simplify right side
    215.18x = 68,490.83
  5. Step 5: Solve for x
    x = 68,490.83/215.18
  6. Step 6: Final answer
    x = 318.30

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.