Finding the Fourth Proportional to 1,422.05, 1,961.78 and 924.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,422.05 : 1,961.78 = 924.80 : x
2. Step 2: Convert to fraction form
   1,422.05/1,961.78 = 924.80/x
3. Step 3: Cross multiply
   1,422.05x = 1,961.78 × 924.80
4. Step 4: Simplify right side
   1,422.05x = 1,814,239.71
5. Step 5: Solve for x
   x = 1,814,239.71/1,422.05
6. Step 6: Final answer
   x = 1,275.80