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Finding the Fourth Proportional to 427.20, 589.20 and 287.28

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Solution

The fourth proportional to 427.20, 589.20 and 287.28 is: 396.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.20 : 589.20 = 287.28 : x
  2. Step 2: Convert to fraction form
    427.20/589.20 = 287.28/x
  3. Step 3: Cross multiply
    427.20x = 589.20 × 287.28
  4. Step 4: Simplify right side
    427.20x = 169,265.38
  5. Step 5: Solve for x
    x = 169,265.38/427.20
  6. Step 6: Final answer
    x = 396.22

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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.