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Finding the Fourth Proportional to 688.98, 1,033.92 and 643.43

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Solution

The fourth proportional to 688.98, 1,033.92 and 643.43 is: 965.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.98 : 1,033.92 = 643.43 : x
  2. Step 2: Convert to fraction form
    688.98/1,033.92 = 643.43/x
  3. Step 3: Cross multiply
    688.98x = 1,033.92 × 643.43
  4. Step 4: Simplify right side
    688.98x = 665,255.15
  5. Step 5: Solve for x
    x = 665,255.15/688.98
  6. Step 6: Final answer
    x = 965.57

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.