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Finding the Fourth Proportional to 215.85, 321.38 and 214.65

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Solution

The fourth proportional to 215.85, 321.38 and 214.65 is: 319.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    215.85 : 321.38 = 214.65 : x
  2. Step 2: Convert to fraction form
    215.85/321.38 = 214.65/x
  3. Step 3: Cross multiply
    215.85x = 321.38 × 214.65
  4. Step 4: Simplify right side
    215.85x = 68,984.75
  5. Step 5: Solve for x
    x = 68,984.75/215.85
  6. Step 6: Final answer
    x = 319.60

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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.