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Finding the Fourth Proportional to 287.08, 396.21 and 213.28

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Solution

The fourth proportional to 287.08, 396.21 and 213.28 is: 294.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.08 : 396.21 = 213.28 : x
  2. Step 2: Convert to fraction form
    287.08/396.21 = 213.28/x
  3. Step 3: Cross multiply
    287.08x = 396.21 × 213.28
  4. Step 4: Simplify right side
    287.08x = 84,503.67
  5. Step 5: Solve for x
    x = 84,503.67/287.08
  6. Step 6: Final answer
    x = 294.36

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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.