Finding the Fourth Proportional to 21,091, 29,106.45 and 12,138.52

Step by Step Solution

1. Step 1: Write the proportion equation
   21,091 : 29,106.45 = 12,138.52 : x
2. Step 2: Convert to fraction form
   21,091/29,106.45 = 12,138.52/x
3. Step 3: Cross multiply
   21,091x = 29,106.45 × 12,138.52
4. Step 4: Simplify right side
   21,091x = 353,309,225.45
5. Step 5: Solve for x
   x = 353,309,225.45/21,091
6. Step 6: Final answer
   x = 16,751.66