Finding the Fourth Proportional to 1,113.82, 1,536.98 and 641.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,113.82 : 1,536.98 = 641.69 : x
2. Step 2: Convert to fraction form
   1,113.82/1,536.98 = 641.69/x
3. Step 3: Cross multiply
   1,113.82x = 1,536.98 × 641.69
4. Step 4: Simplify right side
   1,113.82x = 986,264.70
5. Step 5: Solve for x
   x = 986,264.70/1,113.82
6. Step 6: Final answer
   x = 885.48