Finding the Fourth Proportional to 1,137.79, 1,573.61 and 980.59

Step by Step Solution

1. Step 1: Write the proportion equation
   1,137.79 : 1,573.61 = 980.59 : x
2. Step 2: Convert to fraction form
   1,137.79/1,573.61 = 980.59/x
3. Step 3: Cross multiply
   1,137.79x = 1,573.61 × 980.59
4. Step 4: Simplify right side
   1,137.79x = 1,543,066.23
5. Step 5: Solve for x
   x = 1,543,066.23/1,137.79
6. Step 6: Final answer
   x = 1,356.20