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Finding the Fourth Proportional to 640.29, 960.25 and 207.21

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Solution

The fourth proportional to 640.29, 960.25 and 207.21 is: 310.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.29 : 960.25 = 207.21 : x
  2. Step 2: Convert to fraction form
    640.29/960.25 = 207.21/x
  3. Step 3: Cross multiply
    640.29x = 960.25 × 207.21
  4. Step 4: Simplify right side
    640.29x = 198,973.40
  5. Step 5: Solve for x
    x = 198,973.40/640.29
  6. Step 6: Final answer
    x = 310.76

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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.