The correct options are
A commom difference is 2
D a10=21
Let a1=a and common difference be d,
Now,
a2+a7−a4=11⇒(a+d)+(a+6d)−(a+3d)=11⇒a+4d=11…(1)
a3+a8=24⇒(a+2d)+(a+7d)=24⇒2a+9d=24…(2)
By solving both the equations, we get :
a=3, d=2∴a7=3+6×2=15∴a10=3+9×2=21