The graph below shows the relationship between two scales used for temperature measurement, Celsius and Fahrenheit.

Which of the following equations represents graph between the Celsius and the Fahrenheit temperature scales?

Revenue generated in an event by a musical band in the city is as per the graph below. How much was amount raised by the band if $12,700$tickets were sold?

A school hired a bus for a picnic for a day. The basic rent for the bus was $₹13,500$ for $300 \mathrm{km}$ and $₹20$ for each additional kilometre. $40$ students went for picnic and distance travelled was $375 \mathrm{km}$

 What was the cost of travel per student ?

Below is a minimal data points between time spent for practice and performance of students in a grade. A linear regression analysis was done to find the correlation between the two variables and based on the best fit, the equation $2x-3y+7=0$ was synthesised. 

What are data points that fit exactly in the equation?

Below is the graph showing the relationship between income of a person and the income tax the person has to pay to the government. The graph has three segments of straight lines. The equations of the lines operates only within the respective intervals $A \mathrm{to} B, B \mathrm{to} C$ and beyond $C$.

Person $P$ is earning $₹ 14 \mathrm{lakhs}$ per annum and person $Q$ is earning $₹ 9 \mathrm{lakhs}$ per annum. How much more tax does person $P$ pay than person $Q$?

A farmer took a loan $₹9,00,000$ for agricultural purpose for annual interest of $6\%$. The loan is to be repaid in monthly instalments with fixed principal amount of $₹10,000$ along with interest for the outstanding principal amount.

Form an equation between two variables $x, y$ where $x$ is the number of months elapsed and $y$ is the monthly instalment. Use the equation to find the minimum number of months post which, his monthly instalment will be equal or fall below $₹12,000$.

A water tank contains $2000 \mathrm{L}$ of water. The tank is being filled $3 \mathrm{L}/\mathrm{s}$ through an incoming pipe and simultaneously water is let out at the rate of $5 \mathrm{L}/\mathrm{s}$.  Form an equation connecting the volume of water in the tank with the passage of time. Also find the time required to get the water in the tank reduced to half of its initial volume.