Question

Answer it fast guys.​

Answer 1

Answer:

n=6

d=10.8

Step-by-step explanation:

a=8

an=62

Sn=210

we know that

an=a+(n-1)d

62=a+(n-1)d......(1)

Now also

Sn=n/2{2a+(n-1)d}

210=n/2{a+a+(n-1)d}

210*2=n(8+62) (putting value from eqn 1)

420=n*70

=> n=420/70

=> n=6

putting value of n in eqn 1

=> 8+(6-1)d=62

=>5d= 62-8

=>d=54/5

=>d=10.8