Finding the Fourth Proportional to 1,978.81, 2,965.70 and 992.00

Step by Step Solution

1. Step 1: Write the proportion equation
   1,978.81 : 2,965.70 = 992.00 : x
2. Step 2: Convert to fraction form
   1,978.81/2,965.70 = 992.00/x
3. Step 3: Cross multiply
   1,978.81x = 2,965.70 × 992.00
4. Step 4: Simplify right side
   1,978.81x = 2,941,984.29
5. Step 5: Solve for x
   x = 2,941,984.29/1,978.81
6. Step 6: Final answer
   x = 1,486.75