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Finding the Fourth Proportional to 640.67, 884.27 and 407.75

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Solution

The fourth proportional to 640.67, 884.27 and 407.75 is: 562.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.67 : 884.27 = 407.75 : x
  2. Step 2: Convert to fraction form
    640.67/884.27 = 407.75/x
  3. Step 3: Cross multiply
    640.67x = 884.27 × 407.75
  4. Step 4: Simplify right side
    640.67x = 360,561.09
  5. Step 5: Solve for x
    x = 360,561.09/640.67
  6. Step 6: Final answer
    x = 562.79

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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.