Finding the Fourth Proportional to 2,645.17, 3,968.61 and 891.03

Step by Step Solution

1. Step 1: Write the proportion equation
   2,645.17 : 3,968.61 = 891.03 : x
2. Step 2: Convert to fraction form
   2,645.17/3,968.61 = 891.03/x
3. Step 3: Cross multiply
   2,645.17x = 3,968.61 × 891.03
4. Step 4: Simplify right side
   2,645.17x = 3,536,150.57
5. Step 5: Solve for x
   x = 3,536,150.57/2,645.17
6. Step 6: Final answer
   x = 1,336.83