Finding the Fourth Proportional to 1,146.51, 1,581.81 and 998.91

Step by Step Solution

1. Step 1: Write the proportion equation
   1,146.51 : 1,581.81 = 998.91 : x
2. Step 2: Convert to fraction form
   1,146.51/1,581.81 = 998.91/x
3. Step 3: Cross multiply
   1,146.51x = 1,581.81 × 998.91
4. Step 4: Simplify right side
   1,146.51x = 1,580,085.83
5. Step 5: Solve for x
   x = 1,580,085.83/1,146.51
6. Step 6: Final answer
   x = 1,378.17