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Finding the Fourth Proportional to 643.61, 961.49 and 410.64

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Solution

The fourth proportional to 643.61, 961.49 and 410.64 is: 613.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.61 : 961.49 = 410.64 : x
  2. Step 2: Convert to fraction form
    643.61/961.49 = 410.64/x
  3. Step 3: Cross multiply
    643.61x = 961.49 × 410.64
  4. Step 4: Simplify right side
    643.61x = 394,826.25
  5. Step 5: Solve for x
    x = 394,826.25/643.61
  6. Step 6: Final answer
    x = 613.46

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.