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Finding the Fourth Proportional to 285.21, 393.84 and 223.65

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Solution

The fourth proportional to 285.21, 393.84 and 223.65 is: 308.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.21 : 393.84 = 223.65 : x
  2. Step 2: Convert to fraction form
    285.21/393.84 = 223.65/x
  3. Step 3: Cross multiply
    285.21x = 393.84 × 223.65
  4. Step 4: Simplify right side
    285.21x = 88,082.32
  5. Step 5: Solve for x
    x = 88,082.32/285.21
  6. Step 6: Final answer
    x = 308.83

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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.