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Finding the Fourth Proportional to 641.64, 884.88 and 420.51

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Solution

The fourth proportional to 641.64, 884.88 and 420.51 is: 579.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.64 : 884.88 = 420.51 : x
  2. Step 2: Convert to fraction form
    641.64/884.88 = 420.51/x
  3. Step 3: Cross multiply
    641.64x = 884.88 × 420.51
  4. Step 4: Simplify right side
    641.64x = 372,100.89
  5. Step 5: Solve for x
    x = 372,100.89/641.64
  6. Step 6: Final answer
    x = 579.92

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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.