Finding the Fourth Proportional to 91,142.78, 136,713.35 and 28,813.30

Step by Step Solution

1. Step 1: Write the proportion equation
   91,142.78 : 136,713.35 = 28,813.30 : x
2. Step 2: Convert to fraction form
   91,142.78/136,713.35 = 28,813.30/x
3. Step 3: Cross multiply
   91,142.78x = 136,713.35 × 28,813.30
4. Step 4: Simplify right side
   91,142.78x = 3,939,162,767.56
5. Step 5: Solve for x
   x = 3,939,162,767.56/91,142.78
6. Step 6: Final answer
   x = 43,219.69