Finding the Fourth Proportional to 142,386.72, 196,478.64 and 78,714.24

Step by Step Solution

1. Step 1: Write the proportion equation
   142,386.72 : 196,478.64 = 78,714.24 : x
2. Step 2: Convert to fraction form
   142,386.72/196,478.64 = 78,714.24/x
3. Step 3: Cross multiply
   142,386.72x = 196,478.64 × 78,714.24
4. Step 4: Simplify right side
   142,386.72x = 15,465,666,823.83
5. Step 5: Solve for x
   x = 15,465,666,823.83/142,386.72
6. Step 6: Final answer
   x = 108,617.34