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Finding the Fourth Proportional to 680.68, 938.64 and 611.80

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Solution

The fourth proportional to 680.68, 938.64 and 611.80 is: 843.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.68 : 938.64 = 611.80 : x
  2. Step 2: Convert to fraction form
    680.68/938.64 = 611.80/x
  3. Step 3: Cross multiply
    680.68x = 938.64 × 611.80
  4. Step 4: Simplify right side
    680.68x = 574,259.95
  5. Step 5: Solve for x
    x = 574,259.95/680.68
  6. Step 6: Final answer
    x = 843.66

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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.