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Finding the Fourth Proportional to 643.98, 888.69 and 364.21

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Solution

The fourth proportional to 643.98, 888.69 and 364.21 is: 502.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.98 : 888.69 = 364.21 : x
  2. Step 2: Convert to fraction form
    643.98/888.69 = 364.21/x
  3. Step 3: Cross multiply
    643.98x = 888.69 × 364.21
  4. Step 4: Simplify right side
    643.98x = 323,669.78
  5. Step 5: Solve for x
    x = 323,669.78/643.98
  6. Step 6: Final answer
    x = 502.61

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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.