Finding the Fourth Proportional to 139,421.99, 209,015.42 and 60,476.78

Step by Step Solution

1. Step 1: Write the proportion equation
   139,421.99 : 209,015.42 = 60,476.78 : x
2. Step 2: Convert to fraction form
   139,421.99/209,015.42 = 60,476.78/x
3. Step 3: Cross multiply
   139,421.99x = 209,015.42 × 60,476.78
4. Step 4: Simplify right side
   139,421.99x = 12,640,578,224.49
5. Step 5: Solve for x
   x = 12,640,578,224.49/139,421.99
6. Step 6: Final answer
   x = 90,664.17