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Finding the Fourth Proportional to 680.30, 1,019.10 and 371.70

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Solution

The fourth proportional to 680.30, 1,019.10 and 371.70 is: 556.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.30 : 1,019.10 = 371.70 : x
  2. Step 2: Convert to fraction form
    680.30/1,019.10 = 371.70/x
  3. Step 3: Cross multiply
    680.30x = 1,019.10 × 371.70
  4. Step 4: Simplify right side
    680.30x = 378,799.47
  5. Step 5: Solve for x
    x = 378,799.47/680.30
  6. Step 6: Final answer
    x = 556.81

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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.