Finding the Fourth Proportional to 1,967.40, 2,947.86 and 1,389.06

Step by Step Solution

1. Step 1: Write the proportion equation
   1,967.40 : 2,947.86 = 1,389.06 : x
2. Step 2: Convert to fraction form
   1,967.40/2,947.86 = 1,389.06/x
3. Step 3: Cross multiply
   1,967.40x = 2,947.86 × 1,389.06
4. Step 4: Simplify right side
   1,967.40x = 4,094,754.41
5. Step 5: Solve for x
   x = 4,094,754.41/1,967.40
6. Step 6: Final answer
   x = 2,081.30