Finding the Fourth Proportional to 1,561.73, 2,155.89 and 994.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,561.73 : 2,155.89 = 994.80 : x
2. Step 2: Convert to fraction form
   1,561.73/2,155.89 = 994.80/x
3. Step 3: Cross multiply
   1,561.73x = 2,155.89 × 994.80
4. Step 4: Simplify right side
   1,561.73x = 2,144,679.37
5. Step 5: Solve for x
   x = 2,144,679.37/1,561.73
6. Step 6: Final answer
   x = 1,373.27