Finding the Fourth Proportional to 1,620.55, 2,235.98 and 957.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,620.55 : 2,235.98 = 957.50 : x
2. Step 2: Convert to fraction form
   1,620.55/2,235.98 = 957.50/x
3. Step 3: Cross multiply
   1,620.55x = 2,235.98 × 957.50
4. Step 4: Simplify right side
   1,620.55x = 2,140,954.05
5. Step 5: Solve for x
   x = 2,140,954.05/1,620.55
6. Step 6: Final answer
   x = 1,321.13