The final temperature of the calorimeter is 34.0 C.
Two heats are involved:
a. the heat released by the combustion reaction ##q_1##.
b. the heat gained by the calorimeter as it warms up ##q_2##.
##q_1 + q_2## = 0
##mH_c + C_calT = 0##
##T = T_f T_i## (where ##f## and ##i## stand for final and initial
##1.785 g (-26.42 kJg^-1) + 5.02 kJC^-1 (T_f 24.62) C = 0##
##-47.16 kJ + 5.02 kJC^-1 T_f – 123.59 kJ = 0##
##5.02 C^-1 T_f = 123.59 + 47.16 = 170.75##
##T_f = 170.75/5.02 C^-1 = 34.0 C##
The final temperature is 34.0 C.
Note: The answer can have only three because that is all you gave for the heat capacity of the calorimeter.. If you need more precision you will have to recalculate.