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Finding the Fourth Proportional to 639.84, 959.85 and 249.77

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Solution

The fourth proportional to 639.84, 959.85 and 249.77 is: 374.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.84 : 959.85 = 249.77 : x
  2. Step 2: Convert to fraction form
    639.84/959.85 = 249.77/x
  3. Step 3: Cross multiply
    639.84x = 959.85 × 249.77
  4. Step 4: Simplify right side
    639.84x = 239,736.94
  5. Step 5: Solve for x
    x = 239,736.94/639.84
  6. Step 6: Final answer
    x = 374.68

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Similar ratio
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1.5x scale

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.