Finding the Fourth Proportional to 2,191.86, 3,279.12 and 1,218.60

Step by Step Solution

1. Step 1: Write the proportion equation
   2,191.86 : 3,279.12 = 1,218.60 : x
2. Step 2: Convert to fraction form
   2,191.86/3,279.12 = 1,218.60/x
3. Step 3: Cross multiply
   2,191.86x = 3,279.12 × 1,218.60
4. Step 4: Simplify right side
   2,191.86x = 3,995,935.63
5. Step 5: Solve for x
   x = 3,995,935.63/2,191.86
6. Step 6: Final answer
   x = 1,823.08