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Finding the Fourth Proportional to 511.31, 705.74 and 290.39

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Solution

The fourth proportional to 511.31, 705.74 and 290.39 is: 400.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.31 : 705.74 = 290.39 : x
  2. Step 2: Convert to fraction form
    511.31/705.74 = 290.39/x
  3. Step 3: Cross multiply
    511.31x = 705.74 × 290.39
  4. Step 4: Simplify right side
    511.31x = 204,934.86
  5. Step 5: Solve for x
    x = 204,934.86/511.31
  6. Step 6: Final answer
    x = 400.80

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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.