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Finding the Fourth Proportional to 643.28, 961.29 and 479.12

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Solution

The fourth proportional to 643.28, 961.29 and 479.12 is: 715.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.28 : 961.29 = 479.12 : x
  2. Step 2: Convert to fraction form
    643.28/961.29 = 479.12/x
  3. Step 3: Cross multiply
    643.28x = 961.29 × 479.12
  4. Step 4: Simplify right side
    643.28x = 460,568.46
  5. Step 5: Solve for x
    x = 460,568.46/643.28
  6. Step 6: Final answer
    x = 715.97

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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.