Finding the Fourth Proportional to 1,131.21, 1,561.17 and 633.84

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.21 : 1,561.17 = 633.84 : x
2. Step 2: Convert to fraction form
   1,131.21/1,561.17 = 633.84/x
3. Step 3: Cross multiply
   1,131.21x = 1,561.17 × 633.84
4. Step 4: Simplify right side
   1,131.21x = 989,528.82
5. Step 5: Solve for x
   x = 989,528.82/1,131.21
6. Step 6: Final answer
   x = 874.76