Finding the Fourth Proportional to 1,211.99, 1,671.63 and 770.03

Step by Step Solution

1. Step 1: Write the proportion equation
   1,211.99 : 1,671.63 = 770.03 : x
2. Step 2: Convert to fraction form
   1,211.99/1,671.63 = 770.03/x
3. Step 3: Cross multiply
   1,211.99x = 1,671.63 × 770.03
4. Step 4: Simplify right side
   1,211.99x = 1,287,196.89
5. Step 5: Solve for x
   x = 1,287,196.89/1,211.99
6. Step 6: Final answer
   x = 1,062.06