Finding the Fourth Proportional to 1,985.71, 2,978.84 and 1,153.16

Step by Step Solution

1. Step 1: Write the proportion equation
   1,985.71 : 2,978.84 = 1,153.16 : x
2. Step 2: Convert to fraction form
   1,985.71/2,978.84 = 1,153.16/x
3. Step 3: Cross multiply
   1,985.71x = 2,978.84 × 1,153.16
4. Step 4: Simplify right side
   1,985.71x = 3,435,080.82
5. Step 5: Solve for x
   x = 3,435,080.82/1,985.71
6. Step 6: Final answer
   x = 1,729.90