Home / 3,138.90-4,708.38-1,288.72

Finding the Fourth Proportional to 3,138.90, 4,708.38 and 1,288.72

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Solution

The fourth proportional to 3,138.90, 4,708.38 and 1,288.72 is: 1,933.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    3,138.90 : 4,708.38 = 1,288.72 : x
  2. Step 2: Convert to fraction form
    3,138.90/4,708.38 = 1,288.72/x
  3. Step 3: Cross multiply
    3,138.90x = 4,708.38 × 1,288.72
  4. Step 4: Simplify right side
    3,138.90x = 6,067,783.47
  5. Step 5: Solve for x
    x = 6,067,783.47/3,138.90
  6. Step 6: Final answer
    x = 1,933.09

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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.