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
141
The single discount equivalent to two successive discounts of 30% and 10% is:
Answer:
37%
Using A + B - AB/100: 30 + 10 - (30 * 10) / 100 = 40 - 3 = 37%.
142
An article is sold at a certain price. If it is sold at 3/4 of that price, there is a loss of 10%. Find the profit percent when sold at the original price.
Answer:
20%
Let original SP be x. New SP = 0.75x. Loss = 10%, so New SP = 90% of CP. 0.75x = 0.90 * CP => CP = 0.75x / 0.90 = x / 1.2. Original Profit = x - CP = x - (x / 1.2) = 0.2x / 1.2. Profit % = ((0.2x / 1.2) / (x / 1.2)) * 100 = 20%.
143
By selling 100 pens, a shopkeeper gains the selling price of 40 pens. Find his gain percent.
Answer:
66.66%
Let SP of 1 pen = 1. Total SP = 100. Gain = 40. CP = SP - Gain = 100 - 40 = 60. Gain % = (Gain / CP) * 100 = (40 / 60) * 100 = 66.66%.
144
If selling price of an article is 4/3 of its cost price, the profit in the transaction is:
Answer:
33.33%
SP = (4/3)CP. Profit = SP - CP = (4/3)CP - CP = (1/3)CP. Profit % = (Profit / CP) * 100 = (1/3) * 100 = 33.33%.
145
A man sells a car to his friend at a 10% loss. If the friend sells it for Rs. 54000 and gains 20%, the original cost price of the car was:
Answer:
Rs. 50000
Friend's SP = 54000. Friend's CP = 54000 / 1.20 = 45000. Man's SP = 45000. Man sold at 10% loss, so Man's CP = 45000 / 0.90 = Rs. 50000.
146
A machine was sold at a gain of 10%. Had it been sold at Rs. 80 less, the seller would have lost 10%. What was the cost price of the machine?
Answer:
Rs. 400
The difference between 10% gain and 10% loss is 20% of the cost price. 20% of CP = Rs. 80. CP = (80 / 20) * 100 = Rs. 400.
147
A merchant marks his goods up by 50% and then offers a discount on the marked price. If he wants to earn a profit of 20%, what should be the discount percentage?
Answer:
20%
Let CP = 100. MP = 150. Desired SP = 120. Discount = MP - SP = 150 - 120 = 30. Discount % = (30 / 150) * 100 = 20%.
148
A dealer offers a cash discount of 20% and still makes a profit of 20%. If the cost price of an item is Rs. 400, what is its marked price?
Answer:
Rs. 600
CP = 400. Desired SP for 20% profit = 400 * 1.20 = 480. Since a 20% discount is offered, SP = 80% of MP. So, 0.8 * MP = 480 => MP = 480 / 0.8 = Rs. 600.
149
A discount of 15% on one article is the same as a discount of 20% on another article. The costs of the two articles can be:
Answer:
Rs. 80, Rs. 60
Let the prices be x and y. 15% of x = 20% of y. So, 15x = 20y => x/y = 20/15 = 4/3. Checking the options, 80/60 = 4/3.
150
By selling an umbrella for Rs. 300, a shopkeeper gains 20%. To gain 30%, he should sell it for:
Answer:
Rs. 325
CP = 300 / 1.20 = Rs. 250. For a 30% gain, SP = 1.30 * 250 = Rs. 325.