Finding the Fourth Proportional to 1,970.61, 2,719.39 and 1,086.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,970.61 : 2,719.39 = 1,086.40 : x
2. Step 2: Convert to fraction form
   1,970.61/2,719.39 = 1,086.40/x
3. Step 3: Cross multiply
   1,970.61x = 2,719.39 × 1,086.40
4. Step 4: Simplify right side
   1,970.61x = 2,954,326.27
5. Step 5: Solve for x
   x = 2,954,326.27/1,970.61
6. Step 6: Final answer
   x = 1,499.19