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Finding the Fourth Proportional to 639.35, 959.28 and 274.13

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Solution

The fourth proportional to 639.35, 959.28 and 274.13 is: 411.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.35 : 959.28 = 274.13 : x
  2. Step 2: Convert to fraction form
    639.35/959.28 = 274.13/x
  3. Step 3: Cross multiply
    639.35x = 959.28 × 274.13
  4. Step 4: Simplify right side
    639.35x = 262,967.43
  5. Step 5: Solve for x
    x = 262,967.43/639.35
  6. Step 6: Final answer
    x = 411.30

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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.