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Finding the Fourth Proportional to 521.70, 720.20 and 325.28

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Solution

The fourth proportional to 521.70, 720.20 and 325.28 is: 449.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.70 : 720.20 = 325.28 : x
  2. Step 2: Convert to fraction form
    521.70/720.20 = 325.28/x
  3. Step 3: Cross multiply
    521.70x = 720.20 × 325.28
  4. Step 4: Simplify right side
    521.70x = 234,261.43
  5. Step 5: Solve for x
    x = 234,261.43/521.70
  6. Step 6: Final answer
    x = 449.03

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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.