The ratio of the number of boys and girls in a school is 3 : 2. If 20% of the boys and 25% of the girls are scholarship holders, then the percentage of the students who do not get the scholarship, is?

Let the selling price of goods by shyam be = ? 100
? Selling price of goods by Ram = ? 75

Now, according to the question.
125% of selling price of goods by Hari = 75
? Selling price of goods by Hari = (100/125) x 75 = ? 60
So, Hari's goods are cheaper than shyam's good by
(40/100) x 100% = 40%

Let maximum marks be N .

According to the question,
75N/100 - 70 = 112 - 32
? 75N/100 = 80 + 70
? 75N/100 = 150
? N = 200

Passing marks = 112 - 32 = 80
(as Rajesh got 112 marks which is 32 more than the passing marks)

? Minimum passing marks percentage
= (80/200) x 100%
= 40%

Gold in 50g of alloy = (80 x 50)/100 = 40 g

Let W gram gold must be added.
Now, according to the question,
(40 + W) / (50 + W) = 90/100

? 100( 40 + W) = 90 (50 + W)
? 10(40 + W) = 9 (50 + W)
? 400 + 10W = 450 + 9W
? W = 450 - 400
? W = 50g
Thus, 50 g of gold must be added to make it 90%

Let a student was awarded in exam = N marks
According to the question,
After re-evaluation his score
? N - N x (40/100) = 96
? N - 2N/5 = 96
? 5N - 2N/5 = 96
? 3N/5 = 96
? N = (5 x 96)/3 = 5 x 32
? N = 160
So, a student was awarded by 160 marks in examination
? Reduced marks after re-evaluation = 160 - 96 = 64

Let usual speed and usual time taken by the jogger are D and T, respectively.
Let his new speed be D'. Then,
DT = (3D'/4)T
? D = 3D'/4
? D' = 4D/3

Thus, he has to increased his speed by
[(4D/3 - D) / D] x 100% .
= 33¹/₃ %

Let price of ghee before increment = ? N

Consumption = 10 kg
Then, expenditure on ghee = ? 10N

After increment,
Expenditure on ghee = 110% of 10N = 11N
Price of ghee = 132% of N = (N x 132)/100 = 33N/25 per kg

? Now consumption = (11N x 25) / 33N kg
= 8¹/₃ kg

Let expenses on wheat be 12N.
Expenses on meat = 17N.
Expenses on vegetables = 3N.
? Total expenses = 32N.

Increased expenses = ? (120% of 12N) + (130% of 17N) + (150% of 3N)]
= ? [(120/100) x 12N] + [(130/100) x 17N] + [(150/100) x 3N]
= ? [72N/5 + 221N/10 + 9N/2]
= ? (144N + 221N + 45N)/10
= ? 410N/10
= ? 41

? Total increase percentage = (9N/32N) x 100 %
= 225/8 %
= 28¹/₈%

In 1998
Let number of students in x = 3k
Number of students in y = 5k and
Number of students in z = 6k

Next year,
number of students in x = 3k + 20% of 3k = 18k/5
Number of students in y = 5k + 10% of 5k = 11k/2
Number of students in z = 6k + 20% of 6k = 36k/5

According to the question,
(18k/5) / (36k/5) = 1/2
Thus, data is insufficient.

Let us assume that Arun uses N units of petrol everyday. so the amount of of petrol in the tank when it is full will be 10N. If he starts using 25% more petrol everyday. then the units of petrol he now use everyday will be
N(1 + 25/100) = 1.25N

So, the number of days his petrol will now last will be equal to (amount of petrol in tank) / (number of units used everyday)
= (10N) / (1.25N) = 10 / 1.25
= 8 days

Total number of students = 480
percentage of total students passed = 75% of total student
= (75 x 480)/100 = 360 students

Now, using the condition from the question.
Let the number of boys be N
Then, 70% of N + 85% of (480 - N) = 360
? [(70 x N)/100] + [85 x (480 - N)]/100 = 360
? 70N - 85N + 40800 = 36000
? 40800 - 36000 = 85N - 70N
? 4800 = 15N
? N = 4800/15 = 320
? There are 320 boys who appeared for the examination,