Finding the Fourth Proportional to 1,362.40, 1,880.88 and 988.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,362.40 : 1,880.88 = 988.99 : x
2. Step 2: Convert to fraction form
   1,362.40/1,880.88 = 988.99/x
3. Step 3: Cross multiply
   1,362.40x = 1,880.88 × 988.99
4. Step 4: Simplify right side
   1,362.40x = 1,860,171.51
5. Step 5: Solve for x
   x = 1,860,171.51/1,362.40
6. Step 6: Final answer
   x = 1,365.36