Finding the Fourth Proportional to 142,690.61, 196,905.42 and 78,156.51

Step by Step Solution

1. Step 1: Write the proportion equation
   142,690.61 : 196,905.42 = 78,156.51 : x
2. Step 2: Convert to fraction form
   142,690.61/196,905.42 = 78,156.51/x
3. Step 3: Cross multiply
   142,690.61x = 196,905.42 × 78,156.51
4. Step 4: Simplify right side
   142,690.61x = 15,389,440,720.37
5. Step 5: Solve for x
   x = 15,389,440,720.37/142,690.61
6. Step 6: Final answer
   x = 107,851.81