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Finding the Fourth Proportional to 643.98, 888.27 and 422.70

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Solution

The fourth proportional to 643.98, 888.27 and 422.70 is: 583.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.98 : 888.27 = 422.70 : x
  2. Step 2: Convert to fraction form
    643.98/888.27 = 422.70/x
  3. Step 3: Cross multiply
    643.98x = 888.27 × 422.70
  4. Step 4: Simplify right side
    643.98x = 375,471.73
  5. Step 5: Solve for x
    x = 375,471.73/643.98
  6. Step 6: Final answer
    x = 583.05

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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.