Finding the Fourth Proportional to 1,405.63, 1,939.80 and 776.14

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.63 : 1,939.80 = 776.14 : x
2. Step 2: Convert to fraction form
   1,405.63/1,939.80 = 776.14/x
3. Step 3: Cross multiply
   1,405.63x = 1,939.80 × 776.14
4. Step 4: Simplify right side
   1,405.63x = 1,505,556.37
5. Step 5: Solve for x
   x = 1,505,556.37/1,405.63
6. Step 6: Final answer
   x = 1,071.09