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Finding the Fourth Proportional to 275.22, 379.85 and 209.61

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Solution

The fourth proportional to 275.22, 379.85 and 209.61 is: 289.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    275.22 : 379.85 = 209.61 : x
  2. Step 2: Convert to fraction form
    275.22/379.85 = 209.61/x
  3. Step 3: Cross multiply
    275.22x = 379.85 × 209.61
  4. Step 4: Simplify right side
    275.22x = 79,619.31
  5. Step 5: Solve for x
    x = 79,619.31/275.22
  6. Step 6: Final answer
    x = 289.29

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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.