Finding the Fourth Proportional to 1,557.72, 2,148.32 and 998.01

Step by Step Solution

1. Step 1: Write the proportion equation
   1,557.72 : 2,148.32 = 998.01 : x
2. Step 2: Convert to fraction form
   1,557.72/2,148.32 = 998.01/x
3. Step 3: Cross multiply
   1,557.72x = 2,148.32 × 998.01
4. Step 4: Simplify right side
   1,557.72x = 2,144,044.84
5. Step 5: Solve for x
   x = 2,144,044.84/1,557.72
6. Step 6: Final answer
   x = 1,376.40