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Finding the Fourth Proportional to 641.08, 884.28 and 420.34

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Solution

The fourth proportional to 641.08, 884.28 and 420.34 is: 579.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.08 : 884.28 = 420.34 : x
  2. Step 2: Convert to fraction form
    641.08/884.28 = 420.34/x
  3. Step 3: Cross multiply
    641.08x = 884.28 × 420.34
  4. Step 4: Simplify right side
    641.08x = 371,698.26
  5. Step 5: Solve for x
    x = 371,698.26/641.08
  6. Step 6: Final answer
    x = 579.80

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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.