Question

if S19 = 95 find t10​

Answer 1

Answer:

t10=5

Step-by-step explanation:

S19=95

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

S19= 19{2a + (19-1)d}/2 = 95

transporting 2 from LHS to RHS

     = 19{2a + (19-1)d} =95*2

     = 19{2a + (19-1)d} = 190

Dividing whole equation by 19 on both sides  

     = {2a + (19-1)d} = 10

     ={2a + 18d} = 10

Dividing whole equation by 2 on both sides      

     = a + 9d=5

Hence 10th term is 5

Answer 2

Answer:

The answer will be 5.

Step-by-step explanation:

Given;

S19 = 95;

For Sn (sum of n no. of terms) we write;

= n(a + al)/2;

or, = n(a + a + d(n -1))/2;

= n(2a + d(n-1)/2;

Thus, S19 = (19){2a + d((19)-1)}/2;

95 = (19){2a + d((19)-1)}/2;

5 = (2a + 18d)/2;

5 = 2(a + 9d)/2;

5 = a + 9d; (i)

Now, tenth term or t10 can be written as;

= a + d(10 - 1);

= a + 9d; (ii)

Thus, from equation (i) and (ii), we can write;

t10 = a + 9d = 5;

t10 = 5.

That's all.