Finding the Fourth Proportional to 99,399.16, 137,173.98 and 56,971

Step by Step Solution

1. Step 1: Write the proportion equation
   99,399.16 : 137,173.98 = 56,971 : x
2. Step 2: Convert to fraction form
   99,399.16/137,173.98 = 56,971/x
3. Step 3: Cross multiply
   99,399.16x = 137,173.98 × 56,971
4. Step 4: Simplify right side
   99,399.16x = 7,814,938,814.58
5. Step 5: Solve for x
   x = 7,814,938,814.58/99,399.16
6. Step 6: Final answer
   x = 78,621.78