Finding the Fourth Proportional to 45,120, 67,689.41 and 13,528.78

Step by Step Solution

1. Step 1: Write the proportion equation
   45,120 : 67,689.41 = 13,528.78 : x
2. Step 2: Convert to fraction form
   45,120/67,689.41 = 13,528.78/x
3. Step 3: Cross multiply
   45,120x = 67,689.41 × 13,528.78
4. Step 4: Simplify right side
   45,120x = 915,755,136.22
5. Step 5: Solve for x
   x = 915,755,136.22/45,120
6. Step 6: Final answer
   x = 20,295.99