Finding the Fourth Proportional to 2,160.30, 2,980.83 and 1,276.05

Step by Step Solution

1. Step 1: Write the proportion equation
   2,160.30 : 2,980.83 = 1,276.05 : x
2. Step 2: Convert to fraction form
   2,160.30/2,980.83 = 1,276.05/x
3. Step 3: Cross multiply
   2,160.30x = 2,980.83 × 1,276.05
4. Step 4: Simplify right side
   2,160.30x = 3,803,688.12
5. Step 5: Solve for x
   x = 3,803,688.12/2,160.30
6. Step 6: Final answer
   x = 1,760.72