Let the total capacity of tank be 90 liters.
Capacity of tank filled in 1 minute by K = 3 liters.
Capacity of tank filled in 1 minute by L = 15 liters.
Therefore, capacity of the tank filled by both K and L in 1 minute = 18 liters.
Hence, time taken by both the pipes to overflow the tank = 90/18 = 5 minutes.

Let Karan’s present age be x years and Shiva’s present age be y years.
Then, according to the first condition,
x - 10 = 3(y - 10) or x - 3y = - 20 ..(1)
Now, Karan’s age after 10 years = (x + 10) years
Shiva’s age after 10 years = (y + 10)
(x + 10) = 2 (y + 10) or x - 2y = 10 ..(2)
Solving (1) and (2), we get x = 70 and y = 30
Karan’s age = 70 years and Shiva’s age = 30 years.

'Maelstrom' refers to a violent and confused state. The word closest in meaning would be 'turmoil', which also means a state of great disturbance.

Let number of boys = x  , Let number of girls = y
Total numbers of students = x + y
(x + y) × 15.8 = 16.4x + 15.4y
0.6x = 0.4y
x/y = 0.4/0.6 = 2/3

 Ratio of boys and girls in the class is 2:3

'Hypothesis' is a word that gives a brief explanation of the concepts based on the limited evidence. The word 'theory' is closest in meaning to it.

Let the age of the daughter today be ‘x’ years.
Mother’s age today = 3x years
After 10 years, we have
3x + 10 = 2(x + 10)
x = 10 years.

India's Lakshya Sen has become the World No 1 Junior Badminton player. He achieved the distinction in the latest rankings of the Badminton World Federation (BWF). Fifteen-year-old is the first shuttler from Uttarakhand to attain the numero uno spot at the international level. Lakshya, who is considered as the shining future star of Indian badminton, moved ahead of Chia Hao Lee of the Chinese Taipei, to attain the top spot. According to BWF current rankings, Lakshya has 16,903 points in eight tournaments he has played in the season. Chia Hao, who is at the second spot, has 16,091 points.

1. In the latest Global 500 rankings of most valuable and powerful brands across the globe, Sundar Pichai’s Google has surpassed Apple to achieve the top position.
2. The Brand Finance Global 500 list published on February 2, 2017 had featured Apple as the top brand for continuous five years.
3. However, for 2017, the ranking revealed that Google’s brand value rose by 24 percent to $109.5bn in 2016. The brand value of Apple on the other hand dropped 27 percent to $107bn.
4. This is for the first time since 2011 that Google has been placed at the top spot. The third place has been occupied by Amazon.
5. The ranking is based upon factors such as marketing investment, familiarity, loyalty, staff satisfaction and corporate reputation.