Finding the Fourth Proportional to 1,987.78, 2,743.16 and 1,091.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,987.78 : 2,743.16 = 1,091.56 : x
2. Step 2: Convert to fraction form
   1,987.78/2,743.16 = 1,091.56/x
3. Step 3: Cross multiply
   1,987.78x = 2,743.16 × 1,091.56
4. Step 4: Simplify right side
   1,987.78x = 2,994,323.73
5. Step 5: Solve for x
   x = 2,994,323.73/1,987.78
6. Step 6: Final answer
   x = 1,506.37