Important Questions with Answer UGC - NET - Mathematial Sciences

Q1. The houses of three sisters lie in the same row, but the middle sister does not live in the middle house. In the morning, the shadow of the eldest sister’s house falls on the youngest sister’s house. What can be concluded for sure?

1. The youngest sister lives in the middle.
2. The eldest sister lives in the middle.
3. Either the youngest or the eldest sister lives in the middle.
4. The youngest sister’s house lies on the east of the middle sister’s house.

Answer: C

Q3. A mine supplies 10000 tons of copper ore, containing an average of 1.5 wt% copper, to a smelter every day. The smelter extracts 80% of the copper from the ore on the same day. What is the production of copper in tons/ day?

1. 80
2. 12
3. 120
4. 150

Answer: C

Q4. A man sells three articles A, B, C and gains 10% on A, 20% on B and loses 10% on C. He breaks even when combined selling prices of A and C are considered, whereas he gains 5% when combined selling prices of B and C are considered. What is his net loss or gain on the sale of all the articles?

1. 10% gain
2. 20% gain
3. 10.66% gain
4. 6.66% gain

Answer: D

Q5. A person completely under sea water tracks the Sun. Compared to an observer above water, which of the following observations would be made by the underwater observer?

1. Neither the time of sunrise or sunset nor the angular span of the horizon changes.
2. Sunrise is delayed, sunset is advanced, but there is no change in the angular span of the horizon.
3. Sunrise and sunset times remain unchanged, but the angular span of the horizon shrinks.
4. The duration of the day and the angular span of the horizon, both decrease.

Answer: C

Q6. A milkman adds 10 litres of water to 90 litres of milk. After selling 1/5th of the total quantity, he adds water equal to the quantity he has sold. The proportion of water to milk he sells now would be

1. 72 : 28
2. 28 : 72
3. 20 : 80
4. 30 : 70

Answer: B

Q7. Two coconuts have spherical space inside their kernels, with the first having an inner diameter twice that of the other. The larger one is half filled with liquid, while the smaller is completely filled. Which of the following statements is correct?

1. The larger coconut contains 4 times the liquid in the smaller qne.
2. The larger coconut contains twice the liquid in the smaller one.
3. The coconuts contain equal volumes of liquid.
4. The smaller coconut contains twice the liquid in the larger one.

Answer: A

Q8. A chocolate salesman is travelling with 3 boxes with 30 chocolates in each box. During his journey he encounters 30 toll booths. Each toll booth inspector takes one chocolate per box that contains chocolate(s), as tax. What is the largest number of chocolates he can be left with after passing through all toll booths?

1. 0
2. 30
3. 25
4. 20

Answer: C

Q9. A tiger usually stalks its prey from a direction that is upwind of the prey. The reason for this is

1. the wind aids its final burst for killing the prey
2. the wind carries the scent of the prey to the tiger and helps the tiger locate the prey easily
3. the upwind area usually has denser vegetation and better camouflage
4. the upwind location aids the tiger by not letting its smell reach the prey

Answer: D

Q10. A cellphone tower radiates 1W power while the handset transmitter radiates 0.1 mW power. The correct comparison of the radiation energy received by your head from a tower 100 m away (E 1 ) and that from a handset held to your ear (E 2 ) is

1. E 1 >> E 2
2. E 2 >> E 1
3. E 1 = E 2 for communication to be established
4. insufficient data even for a rough comparison

Answer: B