Finding the Fourth Proportional to 1,052.77, 1,577.27 and 641.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,052.77 : 1,577.27 = 641.69 : x
2. Step 2: Convert to fraction form
   1,052.77/1,577.27 = 641.69/x
3. Step 3: Cross multiply
   1,052.77x = 1,577.27 × 641.69
4. Step 4: Simplify right side
   1,052.77x = 1,012,118.39
5. Step 5: Solve for x
   x = 1,012,118.39/1,052.77
6. Step 6: Final answer
   x = 961.39