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Finding the Fourth Proportional to 639.70, 880.88 and 568.77

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Solution

The fourth proportional to 639.70, 880.88 and 568.77 is: 783.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.70 : 880.88 = 568.77 : x
  2. Step 2: Convert to fraction form
    639.70/880.88 = 568.77/x
  3. Step 3: Cross multiply
    639.70x = 880.88 × 568.77
  4. Step 4: Simplify right side
    639.70x = 501,016.93
  5. Step 5: Solve for x
    x = 501,016.93/639.70
  6. Step 6: Final answer
    x = 783.21

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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.