The new acceleration will be 8 m/s²
Acceleration of the object = 12 m/s²
New Net Force of the object = 2 Force
New Mass of the object = 3 Mass
To find new acceleration:
[tex] \frac{f1}{f 2} = \frac{m1 \: m2}{m2 \: a2} [/tex]
[tex] \frac{f}{2f} = \frac{m(12)}{(3m)a2} [/tex]
[tex] \frac{1}{2} = \frac{4}{a2} [/tex]
a2 = 8 m/s²
I hope this helps. :-D :-)
Do comment if you don't understand