Dr. Lal And Jain Solutions for Exercise 8: Quantitative Aptitude

In this equation two equations numbered I and II are given. You have to solve both the equations and mark the appropriate option.

$I. 12x^2-23x+11=0$

$II. 21y^2-20y+4=0$

In this equation two equations numbered I and II are given. You have to solve both the equations and mark the appropriate option.

$I. x^2+12x+35=0$

$II. 7y^2+32y+16=0$

In this equation two equations numbered I and II are given. You have to solve both the equations and mark the appropriate option.

$I. 25x^2+20x+3=0$

$II. 4y^2+11y+6=0$

A number is such that when it is multiplied by $6$, it gives another number which is more than $168$ as the original number itself is less than $168$. What is $15\%$ of the original number?

Dharma invested $₹P$ for $3$ years in scheme A which offered $12\%$ p.a simple interest. She also invested $₹P+400$ in scheme B which offered $10\%$ compound (compounded annually), for $2$ years. If the amount received from scheme A was less than that received from scheme B, by $₹304$, what is the value of P?

Per cent profit earned when an article is sold for $₹558$ is double the per cent profit earned when the same article is sold for $₹504$. If the marked price of the same article is $30\%$ above the cost price, what is the marked price of the article?

In a bag, there are $8$ red balls and $7$ green balls. Three balls are picked at random. What is the probability that two balls are red and one ball is green in colour?

A vessel contains $120$litres mixture of milk and water in the respective ratio $11:4$. Forty-five litres of mixture was taken out and replaced with $5$ liters of water. What is percentage of water in the resultant mixture?