Question

opt question please solve it fast its urgent

Answer 1

ur answer is with my above attachment....

Answer 2

Sum of first 3 numbers=3/2[2a+(n-1)d]
=3/2[2a+2d]=3(a+d)=42
= a+d=42/3
= a+d=14
Sum of first five numbers=5/2[2a+(n-1)d]
= 5/2[2a+4d]=5(a+2d)=80
= a+2d=80/5
= a+2d=16 a=16-2d
=16-2d+d=14
=-d=-2 d=2
= a=14-2=12
20th term=a+19d
=12+19x2=50