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Finding the Fourth Proportional to 1,378.56, 2,067.81 and 830.87

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Solution

The fourth proportional to 1,378.56, 2,067.81 and 830.87 is: 1,246.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,378.56 : 2,067.81 = 830.87 : x
  2. Step 2: Convert to fraction form
    1,378.56/2,067.81 = 830.87/x
  3. Step 3: Cross multiply
    1,378.56x = 2,067.81 × 830.87
  4. Step 4: Simplify right side
    1,378.56x = 1,718,081.29
  5. Step 5: Solve for x
    x = 1,718,081.29/1,378.56
  6. Step 6: Final answer
    x = 1,246.29

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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.