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Finding the Fourth Proportional to 640.72, 961.08 and 316.09

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Solution

The fourth proportional to 640.72, 961.08 and 316.09 is: 474.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.72 : 961.08 = 316.09 : x
  2. Step 2: Convert to fraction form
    640.72/961.08 = 316.09/x
  3. Step 3: Cross multiply
    640.72x = 961.08 × 316.09
  4. Step 4: Simplify right side
    640.72x = 303,787.78
  5. Step 5: Solve for x
    x = 303,787.78/640.72
  6. Step 6: Final answer
    x = 474.14

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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.