Finding the Fourth Proportional to 1,191.78, 1,786.02 and 1,061.64

Step by Step Solution

1. Step 1: Write the proportion equation
   1,191.78 : 1,786.02 = 1,061.64 : x
2. Step 2: Convert to fraction form
   1,191.78/1,786.02 = 1,061.64/x
3. Step 3: Cross multiply
   1,191.78x = 1,786.02 × 1,061.64
4. Step 4: Simplify right side
   1,191.78x = 1,896,110.27
5. Step 5: Solve for x
   x = 1,896,110.27/1,191.78
6. Step 6: Final answer
   x = 1,590.99