Finding the Fourth Proportional to 1,142.51, 1,572.71 and 985.67

Step by Step Solution

1. Step 1: Write the proportion equation
   1,142.51 : 1,572.71 = 985.67 : x
2. Step 2: Convert to fraction form
   1,142.51/1,572.71 = 985.67/x
3. Step 3: Cross multiply
   1,142.51x = 1,572.71 × 985.67
4. Step 4: Simplify right side
   1,142.51x = 1,550,173.07
5. Step 5: Solve for x
   x = 1,550,173.07/1,142.51
6. Step 6: Final answer
   x = 1,356.81