Answer
Tension
T = 20.847 N
Work Step by Step
Equation of motion for m2
m2g - T = m2 (a)
Equation of motion for m1
T-m1gsin30 = m1 (a)
solving two equation we have
a = (m2-m1sin30 )g/ (m1+m2)
a = 0.73575 m/s^2
So we have
T = m2 (g-a)
T = 20.847 N