Finding the Fourth Proportional to 1,373.40, 2,055.30 and 1,123.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,373.40 : 2,055.30 = 1,123.72 : x
2. Step 2: Convert to fraction form
   1,373.40/2,055.30 = 1,123.72/x
3. Step 3: Cross multiply
   1,373.40x = 2,055.30 × 1,123.72
4. Step 4: Simplify right side
   1,373.40x = 2,309,581.72
5. Step 5: Solve for x
   x = 2,309,581.72/1,373.40
6. Step 6: Final answer
   x = 1,681.65