Finding the Fourth Proportional to 2,100.40, 3,151.31 and 930.24

Step by Step Solution

1. Step 1: Write the proportion equation
   2,100.40 : 3,151.31 = 930.24 : x
2. Step 2: Convert to fraction form
   2,100.40/3,151.31 = 930.24/x
3. Step 3: Cross multiply
   2,100.40x = 3,151.31 × 930.24
4. Step 4: Simplify right side
   2,100.40x = 2,931,469.96
5. Step 5: Solve for x
   x = 2,931,469.96/2,100.40
6. Step 6: Final answer
   x = 1,395.68