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Finding the Fourth Proportional to 427.78, 590.10 and 287.65

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Solution

The fourth proportional to 427.78, 590.10 and 287.65 is: 396.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.78 : 590.10 = 287.65 : x
  2. Step 2: Convert to fraction form
    427.78/590.10 = 287.65/x
  3. Step 3: Cross multiply
    427.78x = 590.10 × 287.65
  4. Step 4: Simplify right side
    427.78x = 169,743.54
  5. Step 5: Solve for x
    x = 169,743.54/427.78
  6. Step 6: Final answer
    x = 396.80

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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.