Finding the Fourth Proportional to 2,139.93, 3,210.68 and 969.57

Step by Step Solution

1. Step 1: Write the proportion equation
   2,139.93 : 3,210.68 = 969.57 : x
2. Step 2: Convert to fraction form
   2,139.93/3,210.68 = 969.57/x
3. Step 3: Cross multiply
   2,139.93x = 3,210.68 × 969.57
4. Step 4: Simplify right side
   2,139.93x = 3,112,981.43
5. Step 5: Solve for x
   x = 3,112,981.43/2,139.93
6. Step 6: Final answer
   x = 1,454.71