These question will help you in your upcoming competitive exams like SSC, UPSC, Railway, state exams and much more.
1. If 30% of x is 72. Then the value of x is?
a. 220
b. 480
c. 840
d. 240
Answer : d.240
Explanation:
The equation is written as:
\[ \frac{30}{100} \times x = 72 \]
The value of \( x \) will be:
\[ x = \frac{72 \times 100}{30} = 240 \]
2. 2. What is 20% of 25% of 900?
a. 150
b. 30
c. 45
d. 15
Answer : c.45
Explanation:
The equation is solved as:
\[ \frac{20}{100} \times \frac{25}{100} \times 100 = 45 \]
3. If A’s Income is 20 percent more then the B’s Income Then what percent of B’s Income is A’s income?
a. 25
b. 20
c. 80
d. 75
Answer : d.75
Explanation:
Let A income be 100
If A income is 100 then B income will be 125
According to the question :
\[ 125 \times \frac{x}{100} = 100 \]
Solving for \( x \):
\[ x = 100 \times \frac{100}{125} = 80 \]
The B income is 80% of A income.
4. If A’s income is 50% less than the B’s income, then B’s income is what percent more than the A’s income
a. 75%
b. 125%
c. 100%
d. 50%
Answer : c.100%
Explanation:
Let the income of B be 100.
If the income of B is 100 then the income A will be 50.
Thus A income is 50% more than the B income.
5. 5. Aman’s salary was reduced by 10% and then the reduced salary was increased by 10%. His new salary in comparison with his old salary is?
a. 1% more
b. 1% less
c. 2% more
d. 2% less
Answer : b. 1% less
Explanation:
Explanation:
According to the question:
\[ 100 \times \frac{90}{100} \times \frac{110}{100} = 99 \]
Aman’s salary after the change is 99, which is 1% less than the 100.
6. The monthly salary of Aman and Suresh together amount to Rs. 40,000. Aman spends 85% of his salary and Suresh spends 95% of his salary. If their savings are the same then the salary of Aman is?
a. Rs. 10,000
b. Rs. 12,000
c. Rs. 15,000
d. Rs. 5,000
7. In an examination, there were 100 boys and 80 girls. 60% percent of the boys and 50% of the girl were passed. Find the percentage of candidate that were failed?
a. 46.4%
b. 48.4%
c. 44.4%
d. 49.6%
Answer : c. 44.4%
Explanation:
Total number of students = 100+80 = 180
No. of boys passed = 60% of 100 = 60
No. of girls passed = 50% of 80 = 40
Total number of student passed = 60+40 = 100
Total number of students that not passed = 180-100= 80
Percentage of candidate that were failed :
Explanation:
\[ 180 \times \frac{x}{100} = 80 \]
The value of \( x \) will be :
\[ x = 80 \times \frac{100}{180} = 44.4 \]
8. Sachin has to got 40% marks to pass in an examination. He gets 80 marks and fails by 20 marks. Maximum marks are?
a. 200
b. 220
c. 250
d. 300
Answer : c. 250
Explanation:
Explanation:
Let the maximum marks be \( x \).
Total marks needed to be passed in the examination = 80 + 20 = 100
\[ x \times \frac{40}{100} = 100 \]
\[ x = 100 \times \frac{100}{40} = 250 \]
9. A student got 40% marks in maths subject out of 300. How much should he score in the English subject out of 200 if he is to get overall 50% marks?
a. 60%
b. 65%
c. 70%
d. 75%
Answer : b. 65%
Let the percentage in English be \( x \).
Total marks of both subjects = 300 + 200 = 500
Marks he needs to pass in examination is 50% of 500, which is 250.
Marks he gets in Maths is \[ 300 \times \frac{40}{100} = 120 \]
Marks he needs to get in Science is = 250 – 120 = 130.
Let’s see how much percent of 200 is 130:
\[ 200 \times \frac{x}{100} = 130 \]
\[ x = 65 \]
10. The price of petrol is increased by 25%. By how much percent a bike owner should reduce the consumption of the petrol so that the expenditure of the petrol should not be incresed?
a. 25%
b. 50%
c. 30%
d. 20%
Answer : d. 20%
Explanation:
The percentage by which the petrol consumption should be reduced is:
\[ \frac{25 \times 100}{125} = 20\% \]
11. The price of an article is decreased by 20%. By what percent he price of that article should be increased to restore in its previous price.
a. 20%
b. 15%
c. 25%
d. 30%
12. The price of an article is first decreased by 20% and then increased by 30%. If the resulting price of the article is 416rs then the orignal price of the article is ?
a. 400 rs.
b. 405 rs.
c. 410 rs.
d. 390 rs.
Answer : a. 400rs.
Explanation:
Let the original price of the article be x
According to the question:
Explanation:
\[ x \times \frac{80}{100} \times \frac{130}{100} = 416 \]
Solving for \( x \):
\[ x = \frac{416 \times 100 \times 100}{80 \times 130} = 400 \]
13. If the population of a town is 60,000 and its annual increase is 10%. Then its correct population at the end of 3 years will be?
14. A’s salary is increased by 5 percent. If his present salary is 1680rs. then what was his previous salary?
a. 1500rs.
b. 1550rs.
c. 1600rs.
d. 1650rs.
Answer : c. 1600Rs
Explanation:
Let A’s previous salary be \( x \).
\[ x \times \frac{105}{100} = 1680 \]
\[ x = 1680 \times \frac{100}{105} = 1600 \]
15. In a town, the population was 8000. In one year, male population increased by 10% and female population increased by 8% but the total population of the town was increased by 9%. The number of males in the town was?
a. 4000
b. 5000
c. 6000
d. 6500
Answer : a. 4000
Explanation:
Let the number of males in the town be \( x \).
The number of females in the town is \( (8000 – x) \).
According to the question:
\[ x \times \frac{110}{100} + (8000 – x) \times \frac{108}{100} = 8720 \]
\[ 110x + 8000 \times 108 – 108x = 872,000 \]
\[ 2x + 864,000 = 872,000 \]
\[ 2x = 8,000 \]
\[ x = 4,000 \]
16. The value of a machine depreciates every year at the rate of 10% on its value at the beginning of that year. If the current value of machine is 3645rs. then its worth 3 years ago was?
a. 4000
b. 4250
c. 4500
d. 5000
Answer : d. 5000
Explanation:
Let the value of the machine 3 years ago be \( x \).
\[ 3645 = x \times \frac{90}{100} \times \frac{90}{100} \times \frac{90}{100} \]
\[ x = 3645 \times \frac{10}{9} \times \frac{10}{9} \times \frac{10}{9} = 5000 \]
17. The population of a village is 20,000. Out of them one fifth are females and rest of them are males. 20% of the males and 20% of the females are uneducated. What percentage of the population is educated?
a. 60%
b. 65%
c. 70%
d. 80%
Answer : d. 80%
Explanation:
No. of females in town is one-fifth of 20,000, which is 4,000.
No. of males in the town is 20,000 – 4,000 = 16,000.
Uneducated males in the town are: \[ 16,000 \times \frac{20}{100} = 3,200 \]
Uneducated females in the town are: \[ 4,000 \times \frac{20}{100} = 800 \]
Total educated people in the town are: 20,000 – (3,200 + 800) = 16,000.
Percentage of educated people in the town is:
\[ 20,000 \times \frac{x}{100} = 16,000 \]
\[ x = \frac{16,000}{200} = 80 \]
18. What percent of 2.4kg is 48gm?
a. 1%
b. 10%
c. 2%
d. 20%
Answer : c. 2%
Explanation:
By converting 48g to kg, we get 0.048 kg.
\[ 2.4 \times \frac{x}{100} = \frac{48}{1000} \]
\[ x = 2 \]
19. If 125% of x is 100. Then x is?
a. 80
b. 100
c. 120
d. 75
Answer : a. 80
Explanation:
According to the question:
\[ x \times \frac{125}{100} = 100 \]
\[ x = 100 \times \frac{100}{125} = 80 \]
20. If three-fifth of sixty percent of a number is 36, then the number is?
a. 50
b. 75
c. 100
d. 150
Answer : c. 100
Explanation:
According to the question:
\[ \frac{3}{5} \times \frac{60}{100} \times x = 36 \]
Solving for \( x \):
\[ x = 100 \]
If an article is sold for 450 at 20% loss, find the cost price to gain 20% profit.
यदि एक वस्तु को 20% की हानि पर 450 में बेचा जाता है, तो 20% लाभ प्राप्त करने के लिए विक्रय मूल्य ज्ञात कीजिए।
a. 562.5
b. 600
c. 675
d. 700
Answer: c. 675
Solution:
The article has been sold at 20% loss, which means 450 is 80% of the cost price (CP).
Cost Price calculation:
लेख को 20% हानि पर बेचा गया है, जिसका अर्थ है कि 450 क्रय मूल्य (CP) का 80% है।