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Finding the Fourth Proportional to 643.09, 964 and 411.32

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Solution

The fourth proportional to 643.09, 964 and 411.32 is: 616.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.09 : 964 = 411.32 : x
  2. Step 2: Convert to fraction form
    643.09/964 = 411.32/x
  3. Step 3: Cross multiply
    643.09x = 964 × 411.32
  4. Step 4: Simplify right side
    643.09x = 396,512.48
  5. Step 5: Solve for x
    x = 396,512.48/643.09
  6. Step 6: Final answer
    x = 616.57

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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.