Ques 1.
A reduction of 20% in the price of ghee enables a person to get 5.2 kg more for 130Rs. What is the original price of ghee per kg ?
Solution :
130*20/100=26/5.2=5
==>5*100/80=6.25
Ques 2.
A container contains 80 litres of milk , From this container 16 litres of milk was taken out and replaced by water . This action was repeated one more time. What is the amount of milk in container after second replacement?
Solution :
Remaining solution = initial quantity (1 - (taken quantity/initial quantity))^ number of times
Remaining quantity= 80(1-(16/80))^2 = 51.2 liters
Ques 3.
A card is drawn from a pack of playing cards, what is the probability of getting either a black or a black queen?
Solution :
= (26C1+2C1)/52C1
= 14/26=7/13
Ques 4.
The square of a number is greater than 22 times the same number by 48. What is the number ?
Solution :
X^2 = 22X+48
==> X^2-22X-48=0
==>X=24
Ques 5.
The average weight of 32 students of a class was 48.5kg. After 10 new students joined the class, its average weight increased by 2.75kg. What is the average weight of 10 new students who joined the class?
Solution :
Total Weight of 10 members = (2.75×32) + (51.25×10)
Average Of weight of 10 members = 600.5/10=60.05kg
Ques 6.
A shopkeeper bought two varieties of rice , the first 20kgs at Rs 30 per kg and the other 25kgs at Rs 36 per kg .After mixing the two varieties of rice , at what should he sell the mixed to gain 20% profit ?
Solution :
==>(30*20)+(30*25)/45=100/3
100% ------ 100/3
120% ------ X
Selling Price = 40
Ques 7.
A boat can travel 12.6km DownStream in 18 minutes and 8.25km upstream in 15 minutes. What is the speed of the current ?
Solution :
DownStream speed = (12.6*60)/18=42kmph
Upstream Speed = (8.25*60)/15 = 33kmph
speed of current = (42-33)/2 = 4.5kmph
Ques 8.
18 14 12 4 2 ?
Solution :
18-14=4
14-12=2
12-4 = 8
4-2 = 2
2-X = 12
X = -10
Answer = -10
Ques 9.
At a discount of 10% of the entire purchase Ram could have bought 1 more kg of sugar by paying only 5% of the original amount more. How many kilograms of sugar has Ram bought?
Solution :
CP = 100
After 10% discount= 100*90/100% = 90
Now he pays 5% more on actual selling = 100*105% = 105
1kg cost = (105-90) = 15
Total kgs = 90/15 = 6kgs
Ques 10.
I. 2x^2-11x+12=0 II. 2y^2-17y+36=0
Solution :
2x^2-11x+12
=>x=3/2,4
2y^2-17y+36
=> y=4,9/2
x ≤ y
