Finding the Fourth Proportional to 1,981.06, 2,965.38 and 1,321.64

Step by Step Solution

1. Step 1: Write the proportion equation
   1,981.06 : 2,965.38 = 1,321.64 : x
2. Step 2: Convert to fraction form
   1,981.06/2,965.38 = 1,321.64/x
3. Step 3: Cross multiply
   1,981.06x = 2,965.38 × 1,321.64
4. Step 4: Simplify right side
   1,981.06x = 3,919,164.82
5. Step 5: Solve for x
   x = 3,919,164.82/1,981.06
6. Step 6: Final answer
   x = 1,978.32