Finding the Fourth Proportional to 1,991.21, 2,747.78 and 1,107

Step by Step Solution

1. Step 1: Write the proportion equation
   1,991.21 : 2,747.78 = 1,107 : x
2. Step 2: Convert to fraction form
   1,991.21/2,747.78 = 1,107/x
3. Step 3: Cross multiply
   1,991.21x = 2,747.78 × 1,107
4. Step 4: Simplify right side
   1,991.21x = 3,041,792.46
5. Step 5: Solve for x
   x = 3,041,792.46/1,991.21
6. Step 6: Final answer
   x = 1,527.61