Finding the Fourth Proportional to 1,531.90, 2,113.89 and 902.45

Step by Step Solution

1. Step 1: Write the proportion equation
   1,531.90 : 2,113.89 = 902.45 : x
2. Step 2: Convert to fraction form
   1,531.90/2,113.89 = 902.45/x
3. Step 3: Cross multiply
   1,531.90x = 2,113.89 × 902.45
4. Step 4: Simplify right side
   1,531.90x = 1,907,680.03
5. Step 5: Solve for x
   x = 1,907,680.03/1,531.90
6. Step 6: Final answer
   x = 1,245.31