Finding the Fourth Proportional to 1,570.72, 2,167.61 and 872.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,570.72 : 2,167.61 = 872.10 : x
2. Step 2: Convert to fraction form
   1,570.72/2,167.61 = 872.10/x
3. Step 3: Cross multiply
   1,570.72x = 2,167.61 × 872.10
4. Step 4: Simplify right side
   1,570.72x = 1,890,361.84
5. Step 5: Solve for x
   x = 1,890,361.84/1,570.72
6. Step 6: Final answer
   x = 1,203.50