Finding the Fourth Proportional to 1,528.47, 2,106.81 and 1,057.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,528.47 : 2,106.81 = 1,057.05 : x
2. Step 2: Convert to fraction form
   1,528.47/2,106.81 = 1,057.05/x
3. Step 3: Cross multiply
   1,528.47x = 2,106.81 × 1,057.05
4. Step 4: Simplify right side
   1,528.47x = 2,227,003.51
5. Step 5: Solve for x
   x = 2,227,003.51/1,528.47
6. Step 6: Final answer
   x = 1,457.01