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Finding the Fourth Proportional to 287.10, 398.90 and 284.27

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Solution

The fourth proportional to 287.10, 398.90 and 284.27 is: 394.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.10 : 398.90 = 284.27 : x
  2. Step 2: Convert to fraction form
    287.10/398.90 = 284.27/x
  3. Step 3: Cross multiply
    287.10x = 398.90 × 284.27
  4. Step 4: Simplify right side
    287.10x = 113,394.02
  5. Step 5: Solve for x
    x = 113,394.02/287.10
  6. Step 6: Final answer
    x = 394.96

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.