Finding the Fourth Proportional to 2,311.31, 3,189.63 and 1,316.57

Step by Step Solution

1. Step 1: Write the proportion equation
   2,311.31 : 3,189.63 = 1,316.57 : x
2. Step 2: Convert to fraction form
   2,311.31/3,189.63 = 1,316.57/x
3. Step 3: Cross multiply
   2,311.31x = 3,189.63 × 1,316.57
4. Step 4: Simplify right side
   2,311.31x = 4,199,364.59
5. Step 5: Solve for x
   x = 4,199,364.59/2,311.31
6. Step 6: Final answer
   x = 1,816.88