Finding the Fourth Proportional to 139,412.32, 208,837.81 and 64,429.20

Step by Step Solution

1. Step 1: Write the proportion equation
   139,412.32 : 208,837.81 = 64,429.20 : x
2. Step 2: Convert to fraction form
   139,412.32/208,837.81 = 64,429.20/x
3. Step 3: Cross multiply
   139,412.32x = 208,837.81 × 64,429.20
4. Step 4: Simplify right side
   139,412.32x = 13,455,253,028.05
5. Step 5: Solve for x
   x = 13,455,253,028.05/139,412.32
6. Step 6: Final answer
   x = 96,514.09