Finding the Fourth Proportional to 1,185.77, 1,780.17 and 747.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,185.77 : 1,780.17 = 747.15 : x
2. Step 2: Convert to fraction form
   1,185.77/1,780.17 = 747.15/x
3. Step 3: Cross multiply
   1,185.77x = 1,780.17 × 747.15
4. Step 4: Simplify right side
   1,185.77x = 1,330,054.02
5. Step 5: Solve for x
   x = 1,330,054.02/1,185.77
6. Step 6: Final answer
   x = 1,121.68