Mathematics/General Ability MCQs
Topic Notes: Mathematics/General Ability
MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
191
A boy has coins of 50 paise, 25 paise, and 10 paise in the ratio 1 : 2 : 3. If the total amount is Rs. 6.50, find the number of 10 paise coins.
Answer:
15
Let the number of coins be x, 2x, and 3x. Value in paise: 50x + 25(2x) + 10(3x) = 50x + 50x + 30x = 130x paise. Total amount = 650 paise. 130x = 650 => x = 5. Number of 10 paise coins = 3x = 3 * 5 = 15. Wait, 130x = 650 => x=5. 3x=15. Let me re-read: Option b is 15. Oh, I put option d. Let me correct the correct_option to 'b' for 15.
192
A sum of money is divided among A, B, and C in the ratio 2 : 3 : 5. If C gets Rs. 1500 more than A, find the total sum.
Answer:
Rs. 5000
Difference in ratio parts of C and A is 5 - 2 = 3 parts. 3 parts = 1500, so 1 part = 500. Total parts = 2 + 3 + 5 = 10 parts. Total sum = 10 * 500 = Rs. 5000.
193
An amount of Rs. 2430 is divided among A, B, and C such that if their shares are reduced by Rs. 5, Rs. 10, and Rs. 15 respectively, the remainders shall be in the ratio 3 : 4 : 5. What was B's original share?
Answer:
Rs. 810
Remaining total = 2430 - (5 + 10 + 15) = 2400. This is divided in ratio 3:4:5. Sum of ratios = 12. B's remainder share = (4/12) * 2400 = 800. B's original share = 800 + 10 = Rs. 810.
194
The sub-triplicate ratio of 216 : 343 is:
Answer:
6 : 7
The sub-triplicate ratio is the cube root of the given ratio. Cube root of 216 is 6, and cube root of 343 is 7. Thus, 6 : 7.
195
The triplicate ratio of 1 : 4 is:
Answer:
1 : 64
The triplicate ratio is the cube of the original ratio. 1^3 : 4^3 = 1 : 64.
196
Find the sub-duplicate ratio of 81 : 64.
Answer:
9 : 8
The sub-duplicate ratio is the square root of the ratio. sqrt(81) : sqrt(64) = 9 : 8.
197
Which of the following represents the duplicate ratio of 4 : 7?
Answer:
16 : 49
The duplicate ratio is found by squaring each term of the original ratio. For 4 : 7, it is 4^2 : 7^2 = 16 : 49.
198
What is the compounded ratio of 2:3, 6:11, and 11:2?
Answer:
2 : 1
Compounded ratio = (2/3) * (6/11) * (11/2) = (2 * 6 * 11) / (3 * 11 * 2) = 132 / 66 = 2 / 1. The ratio is 2 : 1.
199
In a mixture, the ratio of milk and water is 3:2. If 4 liters of water is added to the mixture, the ratio of milk and water becomes 3:4. Find the initial quantity of milk.
Answer:
6 liters
Let initial milk and water be 3x and 2x. (3x) / (2x + 4) = 3 / 4. 12x = 6x + 12 => 6x = 12 => x = 2. Initial milk = 3x = 6 liters.
200
The ratio of the total amount distributed in all males and females as salary is 6:5, while the ratio of the salary of each male and each female is 2:3. Find the ratio of the number of males and females.
Answer:
9 : 5
Total salary = (Number of people) * (Salary of each). Number = Total Salary / Individual Salary. Ratio of males:females = (6/2) : (5/3) = 3 : 5/3 = 9 : 5.