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Finding the Fourth Proportional to 511.35, 705.69 and 287.30

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Solution

The fourth proportional to 511.35, 705.69 and 287.30 is: 396.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.35 : 705.69 = 287.30 : x
  2. Step 2: Convert to fraction form
    511.35/705.69 = 287.30/x
  3. Step 3: Cross multiply
    511.35x = 705.69 × 287.30
  4. Step 4: Simplify right side
    511.35x = 202,743.30
  5. Step 5: Solve for x
    x = 202,743.30/511.35
  6. Step 6: Final answer
    x = 396.49

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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.