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Finding the Fourth Proportional to 643.50, 887.79 and 447.42

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Solution

The fourth proportional to 643.50, 887.79 and 447.42 is: 617.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.50 : 887.79 = 447.42 : x
  2. Step 2: Convert to fraction form
    643.50/887.79 = 447.42/x
  3. Step 3: Cross multiply
    643.50x = 887.79 × 447.42
  4. Step 4: Simplify right side
    643.50x = 397,215.00
  5. Step 5: Solve for x
    x = 397,215.00/643.50
  6. Step 6: Final answer
    x = 617.27

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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.