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Finding the Fourth Proportional to 287.31, 396.95 and 285.25

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Solution

The fourth proportional to 287.31, 396.95 and 285.25 is: 394.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.31 : 396.95 = 285.25 : x
  2. Step 2: Convert to fraction form
    287.31/396.95 = 285.25/x
  3. Step 3: Cross multiply
    287.31x = 396.95 × 285.25
  4. Step 4: Simplify right side
    287.31x = 113,229.99
  5. Step 5: Solve for x
    x = 113,229.99/287.31
  6. Step 6: Final answer
    x = 394.10

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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.