Finding the Fourth Proportional to 1,987.31, 2,742.51 and 1,091.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,987.31 : 2,742.51 = 1,091.05 : x
2. Step 2: Convert to fraction form
   1,987.31/2,742.51 = 1,091.05/x
3. Step 3: Cross multiply
   1,987.31x = 2,742.51 × 1,091.05
4. Step 4: Simplify right side
   1,987.31x = 2,992,215.54
5. Step 5: Solve for x
   x = 2,992,215.54/1,987.31
6. Step 6: Final answer
   x = 1,505.66