Question

4. Find the sum of the following by short-cut method: (a) 2096 + 9 (d) 3178 + 99 (b) 4816 + 9 (e) 4196 + 995 (c) 1964 + 99 (f) 30968 + 9996​

Answer 1

Answer:

=49*25= 1225.

Alternatively, you can directly calculate by Sn =(first term+last term) * no of term in progression/2. no of term can calculate by (last term-first term)/d +1 or alternatively you can calculate no of term by, greatest integer of ((last term - first term )/d), where d is term difference.

Sn=(1+49)*49/2= 1225.

for more detail you can refer this

Answer 2

=49*25= 1225.

Alternatively, you can directly calculate by Sn =(first term+last term) * no of term in progression/2. no of term can calculate by (last term-first term)/d +1 or alternatively you can calculate no of term by, greatest integer of ((last term - first term )/d), where d is term difference.

Sn=(1+49)*49/2= 1225.