Finding the Fourth Proportional to 1,987.12, 2,742.22 and 1,147.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,987.12 : 2,742.22 = 1,147.76 : x
2. Step 2: Convert to fraction form
   1,987.12/2,742.22 = 1,147.76/x
3. Step 3: Cross multiply
   1,987.12x = 2,742.22 × 1,147.76
4. Step 4: Simplify right side
   1,987.12x = 3,147,410.43
5. Step 5: Solve for x
   x = 3,147,410.43/1,987.12
6. Step 6: Final answer
   x = 1,583.91