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Finding the Fourth Proportional to 640.91, 961.40 and 230.09

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Solution

The fourth proportional to 640.91, 961.40 and 230.09 is: 345.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.91 : 961.40 = 230.09 : x
  2. Step 2: Convert to fraction form
    640.91/961.40 = 230.09/x
  3. Step 3: Cross multiply
    640.91x = 961.40 × 230.09
  4. Step 4: Simplify right side
    640.91x = 221,202.57
  5. Step 5: Solve for x
    x = 221,202.57/640.91
  6. Step 6: Final answer
    x = 345.14

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.