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Finding the Fourth Proportional to 801.39, 1,200 and 686.57

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Solution

The fourth proportional to 801.39, 1,200 and 686.57 is: 1,028.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    801.39 : 1,200 = 686.57 : x
  2. Step 2: Convert to fraction form
    801.39/1,200 = 686.57/x
  3. Step 3: Cross multiply
    801.39x = 1,200 × 686.57
  4. Step 4: Simplify right side
    801.39x = 823,884.00
  5. Step 5: Solve for x
    x = 823,884.00/801.39
  6. Step 6: Final answer
    x = 1,028.07

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.