Finding the Fourth Proportional to 1,045.51, 1,436.74 and 870.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,045.51 : 1,436.74 = 870.55 : x
2. Step 2: Convert to fraction form
   1,045.51/1,436.74 = 870.55/x
3. Step 3: Cross multiply
   1,045.51x = 1,436.74 × 870.55
4. Step 4: Simplify right side
   1,045.51x = 1,250,748.24
5. Step 5: Solve for x
   x = 1,250,748.24/1,045.51
6. Step 6: Final answer
   x = 1,196.31