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Finding the Fourth Proportional to 511.87, 706.35 and 287.80

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Solution

The fourth proportional to 511.87, 706.35 and 287.80 is: 397.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.87 : 706.35 = 287.80 : x
  2. Step 2: Convert to fraction form
    511.87/706.35 = 287.80/x
  3. Step 3: Cross multiply
    511.87x = 706.35 × 287.80
  4. Step 4: Simplify right side
    511.87x = 203,290.82
  5. Step 5: Solve for x
    x = 203,290.82/511.87
  6. Step 6: Final answer
    x = 397.15

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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.