Finding the Fourth Proportional to 1,553.51, 2,142.91 and 986.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,553.51 : 2,142.91 = 986.15 : x
2. Step 2: Convert to fraction form
   1,553.51/2,142.91 = 986.15/x
3. Step 3: Cross multiply
   1,553.51x = 2,142.91 × 986.15
4. Step 4: Simplify right side
   1,553.51x = 2,113,233.59
5. Step 5: Solve for x
   x = 2,113,233.59/1,553.51
6. Step 6: Final answer
   x = 1,360.29