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Finding the Fourth Proportional to 279.91, 385.79 and 205.12

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Solution

The fourth proportional to 279.91, 385.79 and 205.12 is: 282.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.91 : 385.79 = 205.12 : x
  2. Step 2: Convert to fraction form
    279.91/385.79 = 205.12/x
  3. Step 3: Cross multiply
    279.91x = 385.79 × 205.12
  4. Step 4: Simplify right side
    279.91x = 79,133.24
  5. Step 5: Solve for x
    x = 79,133.24/279.91
  6. Step 6: Final answer
    x = 282.71

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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.