1. The number (6n²+ 6n) for natural n is always divisible by

2. The cost of preparing a cricket ground of rectangular shape at 70 paisa per square meter is Tk. 420. Find the perimeter of the field if its sides are in the ratio of 3 : 2.

3. In order to pass an examination, a student is required to get 35% of the maximum marks. If a student scored a total of 381 marks and failed by 144 marks, determine the maximum marks for the examination.

4. The difference between the compound interest and simple interest on a certain amount of money at 5% per annum for 2 years is Tk. 15. Find the principal amount.

5. A man has Tk. 210 in coins alone. The coins consist of one taka, 50 paisa and whose numbers form a ratio of 5 : 6 : 8 respectively. How many coins are there in the 50 paisa denomination?

6. A tea merchant blends 2 kinds of tea, putting in 3 parts of a Tk. 25 per kg grade to 1 part of a Tk. 15 per kg. If the mixture is changed to 1 part of the Tk. 25 per kg grade to 3 parts of the less expensive grade, how much will the shop lose or save in blending 200 kg?

7. A shopkeeper sells a pair of sunglasses at a profit of 25%. If he had bought it at 25% less and sold it for Tk. 10 less, he would have gained 40%. Determine the cost price of the pair of sunglasses.

8. A culprit was spotted by a policeman from a distance of 250 meter. When the policeman started running towards the culprit at a speed of 10 km/h, the culprit also fled. If his speed was 8 km/h, find how far the culprit had run before he was overpowered.