Finding the Fourth Proportional to 1,981.56, 2,970.72 and 828.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,981.56 : 2,970.72 = 828.12 : x
2. Step 2: Convert to fraction form
   1,981.56/2,970.72 = 828.12/x
3. Step 3: Cross multiply
   1,981.56x = 2,970.72 × 828.12
4. Step 4: Simplify right side
   1,981.56x = 2,460,112.65
5. Step 5: Solve for x
   x = 2,460,112.65/1,981.56
6. Step 6: Final answer
   x = 1,241.50