Finding the Fourth Proportional to 2,655.40, 3,980.35 and 899.82

Step by Step Solution

1. Step 1: Write the proportion equation
   2,655.40 : 3,980.35 = 899.82 : x
2. Step 2: Convert to fraction form
   2,655.40/3,980.35 = 899.82/x
3. Step 3: Cross multiply
   2,655.40x = 3,980.35 × 899.82
4. Step 4: Simplify right side
   2,655.40x = 3,581,594.04
5. Step 5: Solve for x
   x = 3,581,594.04/2,655.40
6. Step 6: Final answer
   x = 1,348.80