Finding the Fourth Proportional to 1,967.60, 2,715.24 and 1,128.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,967.60 : 2,715.24 = 1,128.80 : x
2. Step 2: Convert to fraction form
   1,967.60/2,715.24 = 1,128.80/x
3. Step 3: Cross multiply
   1,967.60x = 2,715.24 × 1,128.80
4. Step 4: Simplify right side
   1,967.60x = 3,064,962.91
5. Step 5: Solve for x
   x = 3,064,962.91/1,967.60
6. Step 6: Final answer
   x = 1,557.72