Finding the Fourth Proportional to 1,205.56, 1,663.72 and 786.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,205.56 : 1,663.72 = 786.12 : x
2. Step 2: Convert to fraction form
   1,205.56/1,663.72 = 786.12/x
3. Step 3: Cross multiply
   1,205.56x = 1,663.72 × 786.12
4. Step 4: Simplify right side
   1,205.56x = 1,307,883.57
5. Step 5: Solve for x
   x = 1,307,883.57/1,205.56
6. Step 6: Final answer
   x = 1,084.88