Finding the Fourth Proportional to 218,131.68, 326,613.98 and 128,100.18

Step by Step Solution

1. Step 1: Write the proportion equation
   218,131.68 : 326,613.98 = 128,100.18 : x
2. Step 2: Convert to fraction form
   218,131.68/326,613.98 = 128,100.18/x
3. Step 3: Cross multiply
   218,131.68x = 326,613.98 × 128,100.18
4. Step 4: Simplify right side
   218,131.68x = 41,839,309,628.52
5. Step 5: Solve for x
   x = 41,839,309,628.52/218,131.68
6. Step 6: Final answer
   x = 191,807.58