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Finding the Fourth Proportional to 639.84, 883.29 and 377.80

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Solution

The fourth proportional to 639.84, 883.29 and 377.80 is: 521.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.84 : 883.29 = 377.80 : x
  2. Step 2: Convert to fraction form
    639.84/883.29 = 377.80/x
  3. Step 3: Cross multiply
    639.84x = 883.29 × 377.80
  4. Step 4: Simplify right side
    639.84x = 333,706.96
  5. Step 5: Solve for x
    x = 333,706.96/639.84
  6. Step 6: Final answer
    x = 521.55

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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.