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Finding the Fourth Proportional to 320, 441.80 and 209.78

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Solution

The fourth proportional to 320, 441.80 and 209.78 is: 289.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    320 : 441.80 = 209.78 : x
  2. Step 2: Convert to fraction form
    320/441.80 = 209.78/x
  3. Step 3: Cross multiply
    320x = 441.80 × 209.78
  4. Step 4: Simplify right side
    320x = 92,680.80
  5. Step 5: Solve for x
    x = 92,680.80/320
  6. Step 6: Final answer
    x = 289.63

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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.