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Finding the Fourth Proportional to 643.60, 888.52 and 422.86

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Solution

The fourth proportional to 643.60, 888.52 and 422.86 is: 583.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.60 : 888.52 = 422.86 : x
  2. Step 2: Convert to fraction form
    643.60/888.52 = 422.86/x
  3. Step 3: Cross multiply
    643.60x = 888.52 × 422.86
  4. Step 4: Simplify right side
    643.60x = 375,719.57
  5. Step 5: Solve for x
    x = 375,719.57/643.60
  6. Step 6: Final answer
    x = 583.78

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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.