Finding the Fourth Proportional to 52,086.24, 78,123.16 and 13,615.20

Step by Step Solution

1. Step 1: Write the proportion equation
   52,086.24 : 78,123.16 = 13,615.20 : x
2. Step 2: Convert to fraction form
   52,086.24/78,123.16 = 13,615.20/x
3. Step 3: Cross multiply
   52,086.24x = 78,123.16 × 13,615.20
4. Step 4: Simplify right side
   52,086.24x = 1,063,662,448.03
5. Step 5: Solve for x
   x = 1,063,662,448.03/52,086.24
6. Step 6: Final answer
   x = 20,421.18