Finding the Fourth Proportional to 1,091.64, 1,501.56 and 880.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,091.64 : 1,501.56 = 880.50 : x
2. Step 2: Convert to fraction form
   1,091.64/1,501.56 = 880.50/x
3. Step 3: Cross multiply
   1,091.64x = 1,501.56 × 880.50
4. Step 4: Simplify right side
   1,091.64x = 1,322,123.58
5. Step 5: Solve for x
   x = 1,322,123.58/1,091.64
6. Step 6: Final answer
   x = 1,211.14