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Finding the Fourth Proportional to 643.59, 894.32 and 636.90

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Solution

The fourth proportional to 643.59, 894.32 and 636.90 is: 885.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.59 : 894.32 = 636.90 : x
  2. Step 2: Convert to fraction form
    643.59/894.32 = 636.90/x
  3. Step 3: Cross multiply
    643.59x = 894.32 × 636.90
  4. Step 4: Simplify right side
    643.59x = 569,589.22
  5. Step 5: Solve for x
    x = 569,589.22/643.59
  6. Step 6: Final answer
    x = 885.02

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.