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Finding the Fourth Proportional to 640.68, 884.37 and 419.68

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Solution

The fourth proportional to 640.68, 884.37 and 419.68 is: 579.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.68 : 884.37 = 419.68 : x
  2. Step 2: Convert to fraction form
    640.68/884.37 = 419.68/x
  3. Step 3: Cross multiply
    640.68x = 884.37 × 419.68
  4. Step 4: Simplify right side
    640.68x = 371,152.40
  5. Step 5: Solve for x
    x = 371,152.40/640.68
  6. Step 6: Final answer
    x = 579.31

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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.