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Finding the Fourth Proportional to 640.82, 885.66 and 511.22

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Solution

The fourth proportional to 640.82, 885.66 and 511.22 is: 706.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.82 : 885.66 = 511.22 : x
  2. Step 2: Convert to fraction form
    640.82/885.66 = 511.22/x
  3. Step 3: Cross multiply
    640.82x = 885.66 × 511.22
  4. Step 4: Simplify right side
    640.82x = 452,767.11
  5. Step 5: Solve for x
    x = 452,767.11/640.82
  6. Step 6: Final answer
    x = 706.54

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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.