Finding the Fourth Proportional to 2,990.79, 4,485.74 and 1,142.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,990.79 : 4,485.74 = 1,142.78 : x
2. Step 2: Convert to fraction form
   2,990.79/4,485.74 = 1,142.78/x
3. Step 3: Cross multiply
   2,990.79x = 4,485.74 × 1,142.78
4. Step 4: Simplify right side
   2,990.79x = 5,126,185.81
5. Step 5: Solve for x
   x = 5,126,185.81/2,990.79
6. Step 6: Final answer
   x = 1,713.99