Finding the Fourth Proportional to 1,570.74, 2,167.72 and 872.06

Step by Step Solution

1. Step 1: Write the proportion equation
   1,570.74 : 2,167.72 = 872.06 : x
2. Step 2: Convert to fraction form
   1,570.74/2,167.72 = 872.06/x
3. Step 3: Cross multiply
   1,570.74x = 2,167.72 × 872.06
4. Step 4: Simplify right side
   1,570.74x = 1,890,381.90
5. Step 5: Solve for x
   x = 1,890,381.90/1,570.74
6. Step 6: Final answer
   x = 1,203.50