Finding the Fourth Proportional to 1,861.56, 2,791.71 and 765.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,861.56 : 2,791.71 = 765.42 : x
2. Step 2: Convert to fraction form
   1,861.56/2,791.71 = 765.42/x
3. Step 3: Cross multiply
   1,861.56x = 2,791.71 × 765.42
4. Step 4: Simplify right side
   1,861.56x = 2,136,830.67
5. Step 5: Solve for x
   x = 2,136,830.67/1,861.56
6. Step 6: Final answer
   x = 1,147.87