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Finding the Fourth Proportional to 521.98, 720.30 and 289.10

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Solution

The fourth proportional to 521.98, 720.30 and 289.10 is: 398.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.98 : 720.30 = 289.10 : x
  2. Step 2: Convert to fraction form
    521.98/720.30 = 289.10/x
  3. Step 3: Cross multiply
    521.98x = 720.30 × 289.10
  4. Step 4: Simplify right side
    521.98x = 208,238.73
  5. Step 5: Solve for x
    x = 208,238.73/521.98
  6. Step 6: Final answer
    x = 398.94

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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.