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Finding the Fourth Proportional to 640.91, 884.47 and 361.21

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Solution

The fourth proportional to 640.91, 884.47 and 361.21 is: 498.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.91 : 884.47 = 361.21 : x
  2. Step 2: Convert to fraction form
    640.91/884.47 = 361.21/x
  3. Step 3: Cross multiply
    640.91x = 884.47 × 361.21
  4. Step 4: Simplify right side
    640.91x = 319,479.41
  5. Step 5: Solve for x
    x = 319,479.41/640.91
  6. Step 6: Final answer
    x = 498.48

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.