Finding the Fourth Proportional to 1,100.78, 1,518.80 and 708.32

Step by Step Solution

1. Step 1: Write the proportion equation
   1,100.78 : 1,518.80 = 708.32 : x
2. Step 2: Convert to fraction form
   1,100.78/1,518.80 = 708.32/x
3. Step 3: Cross multiply
   1,100.78x = 1,518.80 × 708.32
4. Step 4: Simplify right side
   1,100.78x = 1,075,796.42
5. Step 5: Solve for x
   x = 1,075,796.42/1,100.78
6. Step 6: Final answer
   x = 977.30