0
Q:

In an examination, a student scores 4 marks for every correct answer and loses I mark for every wrong answer. If he attempts in all 60 questions and secures 130 marks, the number of questions he attempts correctly, is:

 A) 35 B) 38 C) 40 D) 42

Explanation:

Let the number of correct answers be X.

Number of incorrect answers = (60 – X).

${\color{Blue}&space;\therefore&space;}$ 4x – (60 – x) = 130

=> 5x = 190  => x = 38

Q:

Simplify the following equation.

$\inline \frac{19}{43}+ \frac{1}{2+\frac{1}{3+\frac{1}{1+\frac{1}{4}}}}$

 A) 43/19 B) 1 C) 38/19 D) None of these

Explanation:

$\inline \frac{19}{43}+ \frac{1}{2+\frac{1}{3+\frac{1}{1+\frac{1}{4}}}}=\frac{19}{43}+ \frac{1}{2+\frac{5}{19}}=\frac{19}{43}+\frac{19}{43}=\frac{38}{43}$

20 1517
Q:

Simplify  $\inline \frac{(1.5)^{3}+(4.7)^{3}+(3.8)^{3}-3\times 1.5\times 4.7\times 3.8}{(1.5)^{2}+(4.7)^{2}+(3.8)^{2}-1.5\times 4.7\times -4.7\times 3.8-1.5\times 3.8}$

 A) 6 B) 8 C) 10 D) 12

Explanation:

Apply $\inline \frac{a^{3}+b^{3}+c^{3}-3abc}{a^{2}+b^{2}+c^{2}-ab-bc-ca}=a+b+c$

13 990
Q:

$\inline 48\sqrt{?}+32\sqrt{?}=320$

 A) 4 B) 8 C) 16 D) 32

Explanation:

$\inline 48\sqrt{?}+32\sqrt{?}=320$

$\inline \Rightarrow 6\sqrt{?}+4\sqrt{?}=40$

$\inline \Rightarrow 36\times ?+16\times ?+48\times ?=1600$

$\inline \Rightarrow 100\times ? =1600$

$\inline \Rightarrow ? =16$

5 1126
Q:

$\inline 17\frac{4}{7}+13\frac{2}{12}-?=11\frac{2}{3}$

 A) 16 B) 17 C) 18 D) 19

Explanation:

$\inline 17\frac{4}{7}+13\frac{2}{12}-?=11\frac{2}{3}$

$\inline \frac{123}{7}+\frac{275}{21}-?=\frac{35}{3}$

$\inline ?= \frac{123}{7}+\frac{275}{21}-\frac{35}{3}$

$\inline = \frac{369+275+-245}{21}=\frac{399}{21}=19$

4 897
Q:

38% of 7500 +  ?% of 375 = 50% of 6000

 A) 50 B) 40 C) 60 D) 45

$\inline \frac{38}{100}\times 7500+\frac{?}{100}\times 375=\frac{50}{100}\times 6000$
$\inline 2850+?\times 3.75=3000$
$\inline ?=\frac{150}{3.75}=40$