Finding the Fourth Proportional to 1,428.56, 1,971.51 and 799.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,428.56 : 1,971.51 = 799.15 : x
2. Step 2: Convert to fraction form
   1,428.56/1,971.51 = 799.15/x
3. Step 3: Cross multiply
   1,428.56x = 1,971.51 × 799.15
4. Step 4: Simplify right side
   1,428.56x = 1,575,520.36
5. Step 5: Solve for x
   x = 1,575,520.36/1,428.56
6. Step 6: Final answer
   x = 1,102.88