Finding the Fourth Proportional to 2,105.36, 3,156.42 and 788.30

Step by Step Solution

1. Step 1: Write the proportion equation
   2,105.36 : 3,156.42 = 788.30 : x
2. Step 2: Convert to fraction form
   2,105.36/3,156.42 = 788.30/x
3. Step 3: Cross multiply
   2,105.36x = 3,156.42 × 788.30
4. Step 4: Simplify right side
   2,105.36x = 2,488,205.89
5. Step 5: Solve for x
   x = 2,488,205.89/2,105.36
6. Step 6: Final answer
   x = 1,181.84