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Finding the Fourth Proportional to 275.85, 380.97 and 209.70

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Solution

The fourth proportional to 275.85, 380.97 and 209.70 is: 289.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    275.85 : 380.97 = 209.70 : x
  2. Step 2: Convert to fraction form
    275.85/380.97 = 209.70/x
  3. Step 3: Cross multiply
    275.85x = 380.97 × 209.70
  4. Step 4: Simplify right side
    275.85x = 79,889.41
  5. Step 5: Solve for x
    x = 79,889.41/275.85
  6. Step 6: Final answer
    x = 289.61

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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.