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Finding the Fourth Proportional to 682.80, 937.02 and 639.60

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Solution

The fourth proportional to 682.80, 937.02 and 639.60 is: 877.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    682.80 : 937.02 = 639.60 : x
  2. Step 2: Convert to fraction form
    682.80/937.02 = 639.60/x
  3. Step 3: Cross multiply
    682.80x = 937.02 × 639.60
  4. Step 4: Simplify right side
    682.80x = 599,317.99
  5. Step 5: Solve for x
    x = 599,317.99/682.80
  6. Step 6: Final answer
    x = 877.74

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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.