Finding the Fourth Proportional to 1,420.45, 1,960.25 and 790.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,420.45 : 1,960.25 = 790.99 : x
2. Step 2: Convert to fraction form
   1,420.45/1,960.25 = 790.99/x
3. Step 3: Cross multiply
   1,420.45x = 1,960.25 × 790.99
4. Step 4: Simplify right side
   1,420.45x = 1,550,534.19
5. Step 5: Solve for x
   x = 1,550,534.19/1,420.45
6. Step 6: Final answer
   x = 1,091.58