Finding the Fourth Proportional to 231,068.16, 318,870 and 129,087

Step by Step Solution

1. Step 1: Write the proportion equation
   231,068.16 : 318,870 = 129,087 : x
2. Step 2: Convert to fraction form
   231,068.16/318,870 = 129,087/x
3. Step 3: Cross multiply
   231,068.16x = 318,870 × 129,087
4. Step 4: Simplify right side
   231,068.16x = 41,161,971,690
5. Step 5: Solve for x
   x = 41,161,971,690/231,068.16
6. Step 6: Final answer
   x = 178,137.79