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Finding the Fourth Proportional to 640.89, 960.03 and 511.11

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Solution

The fourth proportional to 640.89, 960.03 and 511.11 is: 765.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.89 : 960.03 = 511.11 : x
  2. Step 2: Convert to fraction form
    640.89/960.03 = 511.11/x
  3. Step 3: Cross multiply
    640.89x = 960.03 × 511.11
  4. Step 4: Simplify right side
    640.89x = 490,680.93
  5. Step 5: Solve for x
    x = 490,680.93/640.89
  6. Step 6: Final answer
    x = 765.62

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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.