Finding the Fourth Proportional to 1,189.60, 1,642.20 and 796.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,189.60 : 1,642.20 = 796.88 : x
2. Step 2: Convert to fraction form
   1,189.60/1,642.20 = 796.88/x
3. Step 3: Cross multiply
   1,189.60x = 1,642.20 × 796.88
4. Step 4: Simplify right side
   1,189.60x = 1,308,636.34
5. Step 5: Solve for x
   x = 1,308,636.34/1,189.60
6. Step 6: Final answer
   x = 1,100.06