Home / 2,138.08-3,208.56-1,991.20

Finding the Fourth Proportional to 2,138.08, 3,208.56 and 1,991.20

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Solution

The fourth proportional to 2,138.08, 3,208.56 and 1,991.20 is: 2,988.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,138.08 : 3,208.56 = 1,991.20 : x
  2. Step 2: Convert to fraction form
    2,138.08/3,208.56 = 1,991.20/x
  3. Step 3: Cross multiply
    2,138.08x = 3,208.56 × 1,991.20
  4. Step 4: Simplify right side
    2,138.08x = 6,388,884.67
  5. Step 5: Solve for x
    x = 6,388,884.67/2,138.08
  6. Step 6: Final answer
    x = 2,988.14

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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.