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Finding the Fourth Proportional to 521.51, 720.39 and 439.49

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Solution

The fourth proportional to 521.51, 720.39 and 439.49 is: 607.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.51 : 720.39 = 439.49 : x
  2. Step 2: Convert to fraction form
    521.51/720.39 = 439.49/x
  3. Step 3: Cross multiply
    521.51x = 720.39 × 439.49
  4. Step 4: Simplify right side
    521.51x = 316,600.60
  5. Step 5: Solve for x
    x = 316,600.60/521.51
  6. Step 6: Final answer
    x = 607.09

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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.