Finding the Fourth Proportional to 1,986.40, 2,742.06 and 1,200.25

Step by Step Solution

1. Step 1: Write the proportion equation
   1,986.40 : 2,742.06 = 1,200.25 : x
2. Step 2: Convert to fraction form
   1,986.40/2,742.06 = 1,200.25/x
3. Step 3: Cross multiply
   1,986.40x = 2,742.06 × 1,200.25
4. Step 4: Simplify right side
   1,986.40x = 3,291,157.52
5. Step 5: Solve for x
   x = 3,291,157.52/1,986.40
6. Step 6: Final answer
   x = 1,656.85