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Finding the Fourth Proportional to 639.62, 959.34 and 453.74

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Solution

The fourth proportional to 639.62, 959.34 and 453.74 is: 680.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.62 : 959.34 = 453.74 : x
  2. Step 2: Convert to fraction form
    639.62/959.34 = 453.74/x
  3. Step 3: Cross multiply
    639.62x = 959.34 × 453.74
  4. Step 4: Simplify right side
    639.62x = 435,290.93
  5. Step 5: Solve for x
    x = 435,290.93/639.62
  6. Step 6: Final answer
    x = 680.55

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.