Finding the Fourth Proportional to 1,990.17, 2,985.72 and 673.98

Step by Step Solution

1. Step 1: Write the proportion equation
   1,990.17 : 2,985.72 = 673.98 : x
2. Step 2: Convert to fraction form
   1,990.17/2,985.72 = 673.98/x
3. Step 3: Cross multiply
   1,990.17x = 2,985.72 × 673.98
4. Step 4: Simplify right side
   1,990.17x = 2,012,315.57
5. Step 5: Solve for x
   x = 2,012,315.57/1,990.17
6. Step 6: Final answer
   x = 1,011.13