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Finding the Fourth Proportional to 521.82, 720.39 and 398.00

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Solution

The fourth proportional to 521.82, 720.39 and 398.00 is: 549.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.82 : 720.39 = 398.00 : x
  2. Step 2: Convert to fraction form
    521.82/720.39 = 398.00/x
  3. Step 3: Cross multiply
    521.82x = 720.39 × 398.00
  4. Step 4: Simplify right side
    521.82x = 286,711.62
  5. Step 5: Solve for x
    x = 286,711.62/521.82
  6. Step 6: Final answer
    x = 549.45

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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.