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Finding the Fourth Proportional to 639.72, 963.27 and 577.80

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Solution

The fourth proportional to 639.72, 963.27 and 577.80 is: 870.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.72 : 963.27 = 577.80 : x
  2. Step 2: Convert to fraction form
    639.72/963.27 = 577.80/x
  3. Step 3: Cross multiply
    639.72x = 963.27 × 577.80
  4. Step 4: Simplify right side
    639.72x = 556,577.41
  5. Step 5: Solve for x
    x = 556,577.41/639.72
  6. Step 6: Final answer
    x = 870.03

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.