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Finding the Fourth Proportional to 640.66, 884.68 and 405.02

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Solution

The fourth proportional to 640.66, 884.68 and 405.02 is: 559.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.66 : 884.68 = 405.02 : x
  2. Step 2: Convert to fraction form
    640.66/884.68 = 405.02/x
  3. Step 3: Cross multiply
    640.66x = 884.68 × 405.02
  4. Step 4: Simplify right side
    640.66x = 358,313.09
  5. Step 5: Solve for x
    x = 358,313.09/640.66
  6. Step 6: Final answer
    x = 559.29

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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.