Finding the Fourth Proportional to 72,090, 99,483.12 and 40,259.36

Step by Step Solution

1. Step 1: Write the proportion equation
   72,090 : 99,483.12 = 40,259.36 : x
2. Step 2: Convert to fraction form
   72,090/99,483.12 = 40,259.36/x
3. Step 3: Cross multiply
   72,090x = 99,483.12 × 40,259.36
4. Step 4: Simplify right side
   72,090x = 4,005,126,742.00
5. Step 5: Solve for x
   x = 4,005,126,742.00/72,090
6. Step 6: Final answer
   x = 55,557.31