Finding the Fourth Proportional to 20,534.30, 30,738.57 and 13,145.88

Step by Step Solution

1. Step 1: Write the proportion equation
   20,534.30 : 30,738.57 = 13,145.88 : x
2. Step 2: Convert to fraction form
   20,534.30/30,738.57 = 13,145.88/x
3. Step 3: Cross multiply
   20,534.30x = 30,738.57 × 13,145.88
4. Step 4: Simplify right side
   20,534.30x = 404,085,552.59
5. Step 5: Solve for x
   x = 404,085,552.59/20,534.30
6. Step 6: Final answer
   x = 19,678.56