Finding the Fourth Proportional to 72,019.19, 99,386.60 and 40,188.18

Step by Step Solution

1. Step 1: Write the proportion equation
   72,019.19 : 99,386.60 = 40,188.18 : x
2. Step 2: Convert to fraction form
   72,019.19/99,386.60 = 40,188.18/x
3. Step 3: Cross multiply
   72,019.19x = 99,386.60 × 40,188.18
4. Step 4: Simplify right side
   72,019.19x = 3,994,166,742.15
5. Step 5: Solve for x
   x = 3,994,166,742.15/72,019.19
6. Step 6: Final answer
   x = 55,459.75