Question
Two boats A and B start towards each other from two
places, 500 km apart. Speed of the boat A and B in still water are 30 km/h and 20 km/h respectively. If A and B proceeds against and with the stream, respectively then after how much time will they meet?Solution
Let the speed of stream be ‘x’ km/h and they meet after‘t’ hours According to question, Distance covered while going upstream + Distance covered while going downstream = Total distance covered. (30 - x)t + (20 + x)t = 500 30t + 20t = 500 50t = 500 t = 10 hours
If the length of a rectangle is increased by 60%, what would be the percentage decrease (correct to the nearest integer) in the width to maintain the s...
In a college, 70% of the students opted for cultural activities. Among those, 50% participated in music events and the remaining 105 students took part ...
- The cost of tea increased by 25%, so Meena reduced her consumption by 20%. Calculate the percentage change in her expenditure on tea.
A person spent 12.5% of his monthly income on food and 32% of the remaining on rent. If amount spent on rent is Rs 1512, then find the amount spe...
The monthly salary of a person is Rs.30000. He spent a% on rent and (a+5)% on EMI. From the remaining, he spend 45% on Education. Find amount spent on E...
- Anita had 320 candies and Rina had 40 more candies than Anita. Anita gave away 25% of her candies while Rina gave away 35% of hers. How many more/less cand...
A student scores 360 marks out of 600 marks in an examination. Find his percentage of marks.
The population of a city is decreased by 15% in the first year and then increased by 20% in the second year. Find the population of the city at the end...
 In a lock-making factory, 10 percent of the total produced locks were found to be defective, and 80 percent of the non-defective locks were exported. ...
Ravi spends 75% of his monthly salary. If his monthly savings are Rs 6,500, what is his monthly salary?