The following table shows the number of mobile phones sold by four different stores in four different years: Stores2012201320142015P178183205225Q133198220235R284250220198S225243199205 Find the difference between the number of mobile phones sold by store Q in 2013 and store S in 2015.

In a data table, the production of rice for country Q and country R is 60 lakh tons and 54 lakh tons respectively. The production of wheat for country S and country T is 52 lakh tons and 52 lakh tons respectively. What is the ratio of the total production of rice of countries Q and R to the total production of wheat of countries S and T?

In a survey of 5 countries (P, Q, R, S, T), the rice production values are 40, 60, 54, 70, and 51 lakh tons respectively. What is the average production of rice (in lakh tons) across all 5 countries?