Finding the Fourth Proportional to 2,071.81, 2,859.09 and 1,188.12

Step by Step Solution

1. Step 1: Write the proportion equation
   2,071.81 : 2,859.09 = 1,188.12 : x
2. Step 2: Convert to fraction form
   2,071.81/2,859.09 = 1,188.12/x
3. Step 3: Cross multiply
   2,071.81x = 2,859.09 × 1,188.12
4. Step 4: Simplify right side
   2,071.81x = 3,396,942.01
5. Step 5: Solve for x
   x = 3,396,942.01/2,071.81
6. Step 6: Final answer
   x = 1,639.60