Finding the Fourth Proportional to 1,991.61, 2,748.48 and 1,107.47

Step by Step Solution

1. Step 1: Write the proportion equation
   1,991.61 : 2,748.48 = 1,107.47 : x
2. Step 2: Convert to fraction form
   1,991.61/2,748.48 = 1,107.47/x
3. Step 3: Cross multiply
   1,991.61x = 2,748.48 × 1,107.47
4. Step 4: Simplify right side
   1,991.61x = 3,043,859.15
5. Step 5: Solve for x
   x = 3,043,859.15/1,991.61
6. Step 6: Final answer
   x = 1,528.34