Finding the Fourth Proportional to 1,257.02, 1,884.71 and 641.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,257.02 : 1,884.71 = 641.48 : x
2. Step 2: Convert to fraction form
   1,257.02/1,884.71 = 641.48/x
3. Step 3: Cross multiply
   1,257.02x = 1,884.71 × 641.48
4. Step 4: Simplify right side
   1,257.02x = 1,209,003.77
5. Step 5: Solve for x
   x = 1,209,003.77/1,257.02
6. Step 6: Final answer
   x = 961.80