Finding the Fourth Proportional to 12,419.64, 17,136.63 and 7,939.98

Step by Step Solution

1. Step 1: Write the proportion equation
   12,419.64 : 17,136.63 = 7,939.98 : x
2. Step 2: Convert to fraction form
   12,419.64/17,136.63 = 7,939.98/x
3. Step 3: Cross multiply
   12,419.64x = 17,136.63 × 7,939.98
4. Step 4: Simplify right side
   12,419.64x = 136,064,499.47
5. Step 5: Solve for x
   x = 136,064,499.47/12,419.64
6. Step 6: Final answer
   x = 10,955.59