Finding the Fourth Proportional to 1,131.80, 1,561.56 and 690.08

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.80 : 1,561.56 = 690.08 : x
2. Step 2: Convert to fraction form
   1,131.80/1,561.56 = 690.08/x
3. Step 3: Cross multiply
   1,131.80x = 1,561.56 × 690.08
4. Step 4: Simplify right side
   1,131.80x = 1,077,601.32
5. Step 5: Solve for x
   x = 1,077,601.32/1,131.80
6. Step 6: Final answer
   x = 952.11