Finding the Fourth Proportional to 1,123.72, 1,683.34 and 879.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,123.72 : 1,683.34 = 879.10 : x
2. Step 2: Convert to fraction form
   1,123.72/1,683.34 = 879.10/x
3. Step 3: Cross multiply
   1,123.72x = 1,683.34 × 879.10
4. Step 4: Simplify right side
   1,123.72x = 1,479,824.19
5. Step 5: Solve for x
   x = 1,479,824.19/1,123.72
6. Step 6: Final answer
   x = 1,316.90