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Finding the Fourth Proportional to 639.85, 959.79 and 177.63

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Solution

The fourth proportional to 639.85, 959.79 and 177.63 is: 266.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.85 : 959.79 = 177.63 : x
  2. Step 2: Convert to fraction form
    639.85/959.79 = 177.63/x
  3. Step 3: Cross multiply
    639.85x = 959.79 × 177.63
  4. Step 4: Simplify right side
    639.85x = 170,481.81
  5. Step 5: Solve for x
    x = 170,481.81/639.85
  6. Step 6: Final answer
    x = 266.44

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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.