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Finding the Fourth Proportional to 3,078, 4,247.67 and 1,680.78

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Solution

The fourth proportional to 3,078, 4,247.67 and 1,680.78 is: 2,319.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    3,078 : 4,247.67 = 1,680.78 : x
  2. Step 2: Convert to fraction form
    3,078/4,247.67 = 1,680.78/x
  3. Step 3: Cross multiply
    3,078x = 4,247.67 × 1,680.78
  4. Step 4: Simplify right side
    3,078x = 7,139,398.78
  5. Step 5: Solve for x
    x = 7,139,398.78/3,078
  6. Step 6: Final answer
    x = 2,319.49

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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.