DELHI POLICE HEAD CONSTABLE (ALGEBRA) QUANT QUIZ-1

Question 1:

If $9 a^{2}+b^{2}=145$ and $a b=4(a>b, a>0, b>0)$ then the value of $(3 a-b)$ is:

9

10

11

12

Question 2:

If $(2 a+4 b):(a+3 b)=9: 5$, then $(a+b):(a-b)$ is equal to:

$3: 4$

$4: 3$

$3: 2$

$2: 3$

Question 3:

If $a-b=13$ and $a b=19$, then the value of $a^{2}-$ $\mathrm{b}^{2}$ is?

$90 \sqrt{5}$

$85 \sqrt{5}$

$91 \sqrt{5}$

None of these

Question 4:

If $a-b=12$ and $a b=50$ then the value of $(a+$ b) $^{2}$ ?

244

444

344

540

Question 5:

What is the value of $a^{3}+b^{3}+c^{3}-3 a b c$, when $a=95, b=96$ and $c=97$.

896

764

832

864

Question 6:

If $a^{3}+b^{3}=218$ and $a+b=2$, then the value of $a b$ is:

$32$

$-35$

$34$

$-31$

Question 7:

If $a+b=12$ and $a^{3}+b^{3}=600$ then the value of $\frac{a b}{a+b} ?$

$\frac{47}{18}$

$\frac{41}{18}$

$\frac{43}{18}$

None of these

Question 8:

If a : b = 5 : 3 and a-b=2 then value of a + b is -

8

2

3

6

Question 9:

If $a^{3}+b^{3}=218$ and $a+b=2$, then the value of $\frac{1}{a^{3}}+\frac{1}{b^{3}}$ is?

$-\frac{218}{42875}$

$\frac{221}{32875}$

$-\frac{219}{41375}$

$\frac{218}{33775}$

Question 10:

If $(5 x+2 y):(10 x+3 y)=5: 9$, then $\left(2 x^{2}+3 y^{2}\right):\left(4 x^{2}+9 y^{2}\right)=$ ?

1: 3

31:87

91:261

91:263