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Finding the Fourth Proportional to 511.85, 706.38 and 287.80

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Solution

The fourth proportional to 511.85, 706.38 and 287.80 is: 397.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.85 : 706.38 = 287.80 : x
  2. Step 2: Convert to fraction form
    511.85/706.38 = 287.80/x
  3. Step 3: Cross multiply
    511.85x = 706.38 × 287.80
  4. Step 4: Simplify right side
    511.85x = 203,294.73
  5. Step 5: Solve for x
    x = 203,294.73/511.85
  6. Step 6: Final answer
    x = 397.18

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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.