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Finding the Fourth Proportional to 643.06, 886.44 and 422.20

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Solution

The fourth proportional to 643.06, 886.44 and 422.20 is: 581.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.06 : 886.44 = 422.20 : x
  2. Step 2: Convert to fraction form
    643.06/886.44 = 422.20/x
  3. Step 3: Cross multiply
    643.06x = 886.44 × 422.20
  4. Step 4: Simplify right side
    643.06x = 374,254.97
  5. Step 5: Solve for x
    x = 374,254.97/643.06
  6. Step 6: Final answer
    x = 581.99

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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.