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Finding the Fourth Proportional to 639.60, 876.99 and 577.19

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Solution

The fourth proportional to 639.60, 876.99 and 577.19 is: 791.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.60 : 876.99 = 577.19 : x
  2. Step 2: Convert to fraction form
    639.60/876.99 = 577.19/x
  3. Step 3: Cross multiply
    639.60x = 876.99 × 577.19
  4. Step 4: Simplify right side
    639.60x = 506,185.47
  5. Step 5: Solve for x
    x = 506,185.47/639.60
  6. Step 6: Final answer
    x = 791.41

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.