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Finding the Fourth Proportional to 643.90, 888.34 and 422.97

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Solution

The fourth proportional to 643.90, 888.34 and 422.97 is: 583.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.90 : 888.34 = 422.97 : x
  2. Step 2: Convert to fraction form
    643.90/888.34 = 422.97/x
  3. Step 3: Cross multiply
    643.90x = 888.34 × 422.97
  4. Step 4: Simplify right side
    643.90x = 375,741.17
  5. Step 5: Solve for x
    x = 375,741.17/643.90
  6. Step 6: Final answer
    x = 583.54

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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.