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Finding the Fourth Proportional to 680.66, 943.62 and 643.70

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Solution

The fourth proportional to 680.66, 943.62 and 643.70 is: 892.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.66 : 943.62 = 643.70 : x
  2. Step 2: Convert to fraction form
    680.66/943.62 = 643.70/x
  3. Step 3: Cross multiply
    680.66x = 943.62 × 643.70
  4. Step 4: Simplify right side
    680.66x = 607,408.19
  5. Step 5: Solve for x
    x = 607,408.19/680.66
  6. Step 6: Final answer
    x = 892.38

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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.