You are trying hard to finish up the Mathematics paper in the allowed time but finding it difficult to do so. As the time is running out and the invigilator is reminding you after every half an hour, this fuels up your anxiety even more. On the other hand, a class mate of yours wraps up the whole Mathematics paper 30 minutes before the maximum allowed time so you cannot claim that the time allowed for solving the paper was insufficient. However, you would want to know about the way your friend solved the paper much earlier than you did. As your paper involved a lot of fractions solving so there is way to solve them, particularly the improper fractions more simply.
The very first thing that you need to do with the improper fraction is to change it into a mixed number that will make calculation easier such as:
8/3 = 2 2/3
2 2/3 means 2 + 2/3
Now consider the other fraction that you have to add with this one and apply the same operation on that fraction in the following way.
7/4 = 1 ¾
1 ¾ means 1 + ¾
After splitting up the two improper fractions whole number and proper fraction, start adding them by first adding up the whole numbers and then the proper fractions.
2 + 1 + 2/3 + ¾
The whole numbers can be added straight way but to add the fractions it is good to equate the denominators by multiplying them with a number such as:
2/3 = 8/12
¾ = 9/12
8/12 + 9/12 = 17/12
Once you have separately added the whole numbers and the fractions, the total calculation can be done easily in the following way:
3 + 17/12 = 36/12 + 17/12 = 53/12