The numbers of boys and girls in a college are in the ratio of 3:2. If 20% of the boys and 25% of the girls are adults, the percentage of students, who are not adults, is
(A) 58%
(B) 60(1/5)%
(C) 78%
(D) 83(1/3)%
To solve this problem, let's first represent the number of boys and girls in terms of a common variable. Let's say there are 3x boys and 2x girls.
Given that 20% of the boys and 25% of the girls are adults, we can calculate the number of adults among them.
Number of adult boys = 20% of 3x = (20/100) * 3x = 0.2 * 3x = 0.6x Number of adult girls = 25% of 2x = (25/100) * 2x = 0.25 * 2x = 0.5x
So, the total number of adult students = 0.6x (boys) + 0.5x (girls) = 1.1x
Now, the total number of students in the college = 3x (boys) + 2x (girls) = 5x
The percentage of students who are not adults = (Total number of non-adult students / Total number of students) * 100%
Since the total number of adult students is 1.1x, the total number of non-adult students = Total number of students - Total number of adult students = 5x - 1.1x = 3.9x
So, the percentage of students who are not adults = (3.9x / 5x) * 100% = (3.9/5) * 100% = 78%
Therefore, the percentage of students who are not adults is 78%.
Imran borrowed a sum of money from Jayant at the rate of 8% per annum simple interest for the first four years, 10% per annum for the next six years, and 12% per annum for the period beyond 10 years. If he pays a total of Rs. 12,160 as interest only at the end of 15 years, how much way did he borrow?
(A) 8000
(B) 10,000
(C) 12,000
(D) 9,000
To find the amount Imran borrowed, let's break down the problem step by step.
Let's denote the principal amount borrowed by Imran as P.
For the first four years, the simple interest is calculated at the rate of 8% per annum. So, the interest for the first four years = P * 8% * 4 = 0.08P * 4 = 0.32P
For the next six years, the simple interest is calculated at the rate of 10% per annum. So, the interest for the next six years = P * 10% * 6 = 0.1P * 6 = 0.6P
For the remaining five years (15 years total - 4 years - 6 years = 5 years), the simple interest is calculated at the rate of 12% per annum. So, the interest for the remaining five years = P * 12% * 5 = 0.12P * 5 = 0.6P
The total interest paid by Imran is given as Rs. 12,160.
So, adding up the interest for each period:
Total interest = 0.32P + 0.6P + 0.6P = 1.52P
Given that the total interest is Rs. 12,160, we can set up the equation:
1.52P = 12,160
Now, solve for P:
P = 12,160 / 1.52 P = 8,000
Therefore, Imran borrowed Rs. 8,000.
A fruit seller bought bananas at the rate of 6 for ₹ 15 and sold them at the rate of 4 for ₹ 12, find his profit or loss percentage.
(A) 17%
(B) 19%
(C) 20%
(D) 22%
To find the profit or loss percentage, we first need to calculate the cost price (CP) and the selling price (SP) of the bananas.
Given: Cost price of 6 bananas = ₹ 15 So, cost price of 1 banana = ₹ 15 / 6 = ₹ 2.50
Now, let's calculate the selling price: Selling price of 4 bananas = ₹ 12 So, selling price of 1 banana = ₹ 12 / 4 = ₹ 3.00
Now, we can compare the CP and SP to determine the profit or loss.
If SP > CP, it's a profit. If SP < CP, it's a loss.
Here, CP = ₹ 2.50 SP = ₹ 3.00
So, it's a profit of ₹ 0.50 per banana.
To find the profit percentage: Profit per banana / CP per banana * 100%
Profit per banana = ₹ 3.00 - ₹ 2.50 = ₹ 0.50
Profit percentage = (0.50 / 2.50) * 100% = 20%
Therefore, the fruit seller made a profit of 20%.
In an examination, 92% of the students passed and 480 students failed. If so, how many students appeared in the examination?
(A) 5800
(B) 6200
(C) 6000
(D) 5000
Let's denote the total number of students who appeared in the examination as 𝑥x.
Given that 92% of the students passed, it means 8% failed because the total percentage is 100%.
We can set up the equation:
8% of 𝑥=4808% of x=480To find 8% of 𝑥x, we multiply 𝑥x by 81001008 (which is the same as multiplying by 0.08):
0.08𝑥=4800.08x=480Now, we can solve for 𝑥x:
𝑥=4800.08x=0.08480𝑥=6000x=6000So, 6000 students appeared in the examination.
If the population of a town is 12.000 and the population increases at the rate of 10% per annum, then find the population. after 3 years.
(A) 15,972
(B) 12,200
(C) 11,200
(D) 10,200
To find the population after 3 years given that it increases at a rate of 10% per annum, you can use the formula for exponential growth:
𝑃=𝑃0×(1+𝑟)𝑛P=P0×(1+r)n
Where:
Given:
Substitute these values into the formula:
𝑃=12,000×(1+0.10)3P=12,000×(1+0.10)3
𝑃=12,000×(1.10)3P=12,000×(1.10)3
𝑃=12,000×(1.331)P=12,000×(1.331)
𝑃=15,972P=15,972
So, the population after 3 years would be approximately 15,972.
A dozen notebooks quoted at Rs 125 are available at 20% discount. How many notebooks can be purchased at Rs 75?
(A) 9
(B) 8
(C) 10
(D) 6
In a constituency, 55% of the total voters are male and the remaining are female. If 40% of the males are illiterate and 40% of the females are educated, then the number of illiterate females is what percent (to the nearest decimal) of the number of illiterate males. correct up to the place) are more?
(A) 16.4%
(B) 20.8%
(C) 22.7%
(D) 21.5%
A number P is 20% more than another number Q but 10% less than the number R. The number Q is what percent of the number R?
(A) 90
(B) 75
(C) 80
(D) 85
Gaurav earns Rs 1800 per day. After a few weeks, he starts earning Rs 960 per day. By what percent does his daily income increase?
(A) 14%
(B) 18%
(C) 16%
(D) 20%
A person saves 25% of his income. If his income increases by 20% and his saving remains the same, then what will be the increased percentage of his expenditure?
(A) 26, 2/3
(B) 26
(C) 20
(D) 30
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