You need to bring them to a common denominator by multiplying the numbers below and above the line by the denominator of the other:
[tex]4*15/(7*15) [/tex] and the other one will be [tex]8*7/(15*7)[/tex]
when we calculate we have
60/105 and the other number is 56/106.
now we can add them:
(60+56)/105=116/105= 1 and 11/105 or 1.104....
