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Finding the Fourth Proportional to 521.28, 721.44 and 447.84

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Solution

The fourth proportional to 521.28, 721.44 and 447.84 is: 619.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.28 : 721.44 = 447.84 : x
  2. Step 2: Convert to fraction form
    521.28/721.44 = 447.84/x
  3. Step 3: Cross multiply
    521.28x = 721.44 × 447.84
  4. Step 4: Simplify right side
    521.28x = 323,089.69
  5. Step 5: Solve for x
    x = 323,089.69/521.28
  6. Step 6: Final answer
    x = 619.80

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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.