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Finding the Fourth Proportional to 640.91, 884.18 and 419.47

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Solution

The fourth proportional to 640.91, 884.18 and 419.47 is: 578.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.91 : 884.18 = 419.47 : x
  2. Step 2: Convert to fraction form
    640.91/884.18 = 419.47/x
  3. Step 3: Cross multiply
    640.91x = 884.18 × 419.47
  4. Step 4: Simplify right side
    640.91x = 370,884.89
  5. Step 5: Solve for x
    x = 370,884.89/640.91
  6. Step 6: Final answer
    x = 578.69

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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.