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Finding the Fourth Proportional to 640.90, 884.08 and 419.46

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Solution

The fourth proportional to 640.90, 884.08 and 419.46 is: 578.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.90 : 884.08 = 419.46 : x
  2. Step 2: Convert to fraction form
    640.90/884.08 = 419.46/x
  3. Step 3: Cross multiply
    640.90x = 884.08 × 419.46
  4. Step 4: Simplify right side
    640.90x = 370,836.20
  5. Step 5: Solve for x
    x = 370,836.20/640.90
  6. Step 6: Final answer
    x = 578.62

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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.