Finding the Fourth Proportional to 1,152.99, 1,591.74 and 780.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,152.99 : 1,591.74 = 780.48 : x
2. Step 2: Convert to fraction form
   1,152.99/1,591.74 = 780.48/x
3. Step 3: Cross multiply
   1,152.99x = 1,591.74 × 780.48
4. Step 4: Simplify right side
   1,152.99x = 1,242,321.24
5. Step 5: Solve for x
   x = 1,242,321.24/1,152.99
6. Step 6: Final answer
   x = 1,077.48