Finding the Fourth Proportional to 1,399.86, 2,097.05 and 1,279.57

Step by Step Solution

1. Step 1: Write the proportion equation
   1,399.86 : 2,097.05 = 1,279.57 : x
2. Step 2: Convert to fraction form
   1,399.86/2,097.05 = 1,279.57/x
3. Step 3: Cross multiply
   1,399.86x = 2,097.05 × 1,279.57
4. Step 4: Simplify right side
   1,399.86x = 2,683,322.27
5. Step 5: Solve for x
   x = 2,683,322.27/1,399.86
6. Step 6: Final answer
   x = 1,916.85