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Finding the Fourth Proportional to 640.84, 890.49 and 634.16

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Solution

The fourth proportional to 640.84, 890.49 and 634.16 is: 881.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.84 : 890.49 = 634.16 : x
  2. Step 2: Convert to fraction form
    640.84/890.49 = 634.16/x
  3. Step 3: Cross multiply
    640.84x = 890.49 × 634.16
  4. Step 4: Simplify right side
    640.84x = 564,713.14
  5. Step 5: Solve for x
    x = 564,713.14/640.84
  6. Step 6: Final answer
    x = 881.21

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.