Explanation:
=$(-\dfrac{9}{7})+(-\dfrac{26}{7})+\dfrac{46}{7}$
=$\dfrac{46}{7}-\dfrac{35}{7}$
=$\dfrac{11}{7}$

Explanation:
The population of a city in the year 2014=1,80,000
Increasing rate in per year=20%
so,the population of the year 2015 =population of 2014 +20%of population of the year 2014
=1,80,000+$(1,80,000\times\dfrac{20}{100})$
=1,80,000+36,000
=2,16,000
then the population of the year 2016=population of 2015+20% of population of the year 2015
=2,16,000+$(2,16,000\times\dfrac{20}{100})$
=2,16,000+43,200
=2,59,200

Explanation:
For this question we have to find the answer directly from the givrn options.
so other than 0 if we put 1,4,6 it'll not be a perfect square.
so if we put 0 then the number is 3025
if we take the square root for 3025=$\sqrt{3025}$
we get,=$(55^{2})$

Explanation:
The average mark of 10 children =80
then their total marks =$10\times 80$
=800marks

Explanation:
work done by a man in one day =$\dfrac{1}{4}$
work done by a woman in one day=$\dfrac{1}{12}$
No.of days to complete the same work by working together=$\dfrac{1}{4}+\dfrac{1}{12}$
=$\dfrac{1+3}{12}$=$\dfrac{4}{12}$=$\dfrac{1}{3}$