Question
A 120-litre mixture contains 25% alcohol. How many
litres of alcohol should be added so that alcohol becomes 40% of the final mixture?Solution
ATQ,
Initial quantity of alcohol = 0.25 × 120 = 30 litres Let the required alcohol to add = y litres So, (30 + y) ÷ (120 + y) = 40/100 = 2/5 ⇒ 5(30 + y) = 2(120 + y) ⇒ 150 + 5y = 240 + 2y ⇒ 3y = 90 ⇒ y = 30
- Find the least 5-digit number which leaves no remainder when divided by 22, 33, 44 and 66.
- The largest 5-digit number which is exactly divisible by ‘47’ is:
Group ‘M’ comprises four even integers in order, and group ‘N’ includes four successive odd integers. If the average of their first elements is ...
How many Zeros can be formed by multiplying 10×20×30×40×…………….× 100
Which of the following is the greatest number that divides 72 and 119 and leaves 3 and 4 as respective remainders?
The difference between the squares of two positive numbers is 18 times the difference between the numbers. If the smaller number is 7, then what is the ...
The value of
3 chairs and 2 tables cost Rs. 700 and 5 chairs and 3 tables cost Rs. 1100. What is the cost of 1 chair and 2 tables?
In a particular examination, Cheenu achieved 48% of the total marks and fell short by 72 marks to pass. On the other hand, Meenu obtained 68% of the tot...
Find the largest three-digit number that leaves '3', '4' and '5' as remainder when it is divided by '7', '8' and '9', respectively.
