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Finding the Fourth Proportional to 640.76, 883.86 and 408.02

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Solution

The fourth proportional to 640.76, 883.86 and 408.02 is: 562.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.76 : 883.86 = 408.02 : x
  2. Step 2: Convert to fraction form
    640.76/883.86 = 408.02/x
  3. Step 3: Cross multiply
    640.76x = 883.86 × 408.02
  4. Step 4: Simplify right side
    640.76x = 360,632.56
  5. Step 5: Solve for x
    x = 360,632.56/640.76
  6. Step 6: Final answer
    x = 562.82

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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.