List of top Data Interpretation & Logical Reasoning (DILR) Questions on Line Graphs asked in CAT

The air-conditioner (AC) in a large room can be operated either in REGULAR mode or in POWER mode to reduce the temperature.
If the AC operates in REGULAR mode, then it brings down the temperature inside the room (called inside temperature) at a constant rate to the set temperature in 1 hour. If it operates in POWER mode, then this is achieved in 30 minutes.
If the AC is switched off, then the inside temperature rises at a constant rate so as to reach the temperature outside at the time of switching off in 1 hour.
The temperature outside has been falling at a constant rate from 7 pm onward until 3 am on a particular night. The following graph shows the inside temperature between 11 pm (23:00) and 2 am (2:00) that night.
graph

The following facts are known about the AC operation that night.
The AC was turned on for the first time that night at 11 pm (23:00).
The AC setting was changed (including turning it on/off, and/or setting different temperatures) only at the beginning of the hour or at 30 minutes after the hour.
The AC was used in POWER mode for longer duration than in REGULAR mode during this 3-hour period.

The following graph represents the variable cost of widgets as a function of quantity produced. The cost of production has two components, variable cost- which is given in the graph, and fixed cost- which is Rs. 800 for the first shift in which 30 widgets can be produced and if more production is desired then a second shift is started which can produce an additional 30 widgets The fixed cost of the second shift is Rs.1200.

These questions are based on the Price Fluctuations of 4 commodities– arhar, pepper, sugar and gold during February– July 1999 as described below:

The following graph shows the sales of the company IVP limited for the years 1994 to 1999. The sales of the company have risen from Rs. 100=00 crores in 1994 to Rs. 680=00 crores in 1999. The Net profit of the company has also gone up from Rs. 2.20 crores in 1994 to Rs. 12=00 crores in the year 1999. Net profit is calculated as surplus sales over the total cost for the company.