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Finding the Fourth Proportional to 512.80, 769.40 and 204.80

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Solution

The fourth proportional to 512.80, 769.40 and 204.80 is: 307.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    512.80 : 769.40 = 204.80 : x
  2. Step 2: Convert to fraction form
    512.80/769.40 = 204.80/x
  3. Step 3: Cross multiply
    512.80x = 769.40 × 204.80
  4. Step 4: Simplify right side
    512.80x = 157,573.12
  5. Step 5: Solve for x
    x = 157,573.12/512.80
  6. Step 6: Final answer
    x = 307.28

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.