Finding the Fourth Proportional to 1,200.40, 1,646.20 and 1,150.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,200.40 : 1,646.20 = 1,150.50 : x
2. Step 2: Convert to fraction form
   1,200.40/1,646.20 = 1,150.50/x
3. Step 3: Cross multiply
   1,200.40x = 1,646.20 × 1,150.50
4. Step 4: Simplify right side
   1,200.40x = 1,893,953.10
5. Step 5: Solve for x
   x = 1,893,953.10/1,200.40
6. Step 6: Final answer
   x = 1,577.77