Finding the Fourth Proportional to 12,181.69, 18,279.83 and 6,991.21

Step by Step Solution

1. Step 1: Write the proportion equation
   12,181.69 : 18,279.83 = 6,991.21 : x
2. Step 2: Convert to fraction form
   12,181.69/18,279.83 = 6,991.21/x
3. Step 3: Cross multiply
   12,181.69x = 18,279.83 × 6,991.21
4. Step 4: Simplify right side
   12,181.69x = 127,798,131.30
5. Step 5: Solve for x
   x = 127,798,131.30/12,181.69
6. Step 6: Final answer
   x = 10,491.00