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Finding the Fourth Proportional to 643.43, 888.79 and 634.02

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Solution

The fourth proportional to 643.43, 888.79 and 634.02 is: 875.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.43 : 888.79 = 634.02 : x
  2. Step 2: Convert to fraction form
    643.43/888.79 = 634.02/x
  3. Step 3: Cross multiply
    643.43x = 888.79 × 634.02
  4. Step 4: Simplify right side
    643.43x = 563,503.02
  5. Step 5: Solve for x
    x = 563,503.02/643.43
  6. Step 6: Final answer
    x = 875.78

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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.