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Finding the Fourth Proportional to 640.81, 884.40 and 361.12

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Solution

The fourth proportional to 640.81, 884.40 and 361.12 is: 498.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.81 : 884.40 = 361.12 : x
  2. Step 2: Convert to fraction form
    640.81/884.40 = 361.12/x
  3. Step 3: Cross multiply
    640.81x = 884.40 × 361.12
  4. Step 4: Simplify right side
    640.81x = 319,371.01
  5. Step 5: Solve for x
    x = 319,371.01/640.81
  6. Step 6: Final answer
    x = 498.38

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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.