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Finding the Fourth Proportional to 680.39, 1,019.66 and 371.78

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Solution

The fourth proportional to 680.39, 1,019.66 and 371.78 is: 557.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.39 : 1,019.66 = 371.78 : x
  2. Step 2: Convert to fraction form
    680.39/1,019.66 = 371.78/x
  3. Step 3: Cross multiply
    680.39x = 1,019.66 × 371.78
  4. Step 4: Simplify right side
    680.39x = 379,089.19
  5. Step 5: Solve for x
    x = 379,089.19/680.39
  6. Step 6: Final answer
    x = 557.16

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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.