Finding the Fourth Proportional to 142,643.53, 196,854.21 and 78,981.31

Step by Step Solution

1. Step 1: Write the proportion equation
   142,643.53 : 196,854.21 = 78,981.31 : x
2. Step 2: Convert to fraction form
   142,643.53/196,854.21 = 78,981.31/x
3. Step 3: Cross multiply
   142,643.53x = 196,854.21 × 78,981.31
4. Step 4: Simplify right side
   142,643.53x = 15,547,803,384.82
5. Step 5: Solve for x
   x = 15,547,803,384.82/142,643.53
6. Step 6: Final answer
   x = 108,997.61