Group1 Previous Year Question Papers Group 1 General Studies 2017 Page: 4
34980.Sum to n terms of an Arithmetic progression is 2n2 + n then eighth term is
136
36
131
31
Explanation:
Let,last term(8th term)=l.
Eighth term be,substitute in question 2( $n^{2}$)+n then
sum of eighth term=2( $8^{2}$)+8=136.
sum of 1st term, =2$(1^{2})$+1=3
a=3.
$s_{n}$=n/2[a+l]=136
8/2[a+l]=136
a+l=136/4=34
l=34-3=31
34982.a,b,c are said to be in Harmonic Progression if their reciprocals $\dfrac{1}{a},\dfrac{1}{b},\dfrac{1}{c}$ are in Arithmetic progression. What would be the value of x for which 3, x, 6 are in Harmonic Progression.
4 1/2
4
5
5 1/2
Explanation:
If a,b,c are in Harmonic,
b is harmonic between a and c.
b=$\dfrac{2ac}{a+c}$
=$\dfrac{2\times3\times6}{9}$
= 4
34984.Value of $\sqrt{3.\sqrt{3.\sqrt[]{3.^{\sqrt{3....}}}}}$
34986.Introducing a girl, Raj said, "Her mother is the only daughter of my mother-in-law". How is Raj related to the girl?
Uncle
Father
Brother
Husband
Explanation:
Since, the mother-in-law of the man is the mother of the lady, therefore, the lady is the daughter of the man
.
34988.A fraction is such that if the numerator is multiplied by 2 and the denominator is reduced by 4 we get $ \dfrac{10}{3} $, but if the numerator is increased by 6 and the denominator is doubled we get $ \dfrac{11}{4} $, what is the fraction?
$ \dfrac{7}{5} $
$ \dfrac{5}{7} $
$ \dfrac{21}{17} $
$ \dfrac{17}{21} $
Explanation:
let fraction =a/b
2a/(b-4)=10/3------> (1)
(a+6)/2b=11/4----->(2)
let check from given option where, a=5, b=7;
check in Equ (1)
2*5/3=10/3
10/3=10/3
check in Equ(2)
5+6/2*7=11/14
11/14=11/14
LHS=RHS
34990.A boy cut a sector containing an angle of 140° from a circle of radius 15 cm and he folded the sector into a cone. What is the curved surface area of the cone {$ \pi=\dfrac{22}{7} $}
572 sq. cm
527 sq. cm
275 sq. cm
257 sq. cm
Explanation:
Area of sector=$\dfrac{\theta}{360^{0}}$
Curved surface area of cone=$\pi$rl
34998.A number is increased by 10% and then decrease by 10%. Find the net decrease percent.
0%
1%
2%
3%
Explanation:
$I-D= \dfrac{I \times D}{100}$
$ =10-10=\dfrac{100}{100}$
$=1%$
35000.A school boy walks from his house to school at the rate of 4 kmph. He reaches the school 20 minutes earlier than the schedule time. If he walks at the rate of 3 kmph, he reaches the school 20 minutes late. What is the distance of the school from his house?
12 km
480 km
21 km
8 km
Explanation:
$Distance= \dfrac{s_{1}\times s_{2}}{s_{1}-s_{2}}\times\dfrac{Difference in time}{60}$
$=\dfrac{4\times3}{1}\times\dfrac{40}{60}$
=$4\times3\times\dfrac{2}{3}$
=8km
35002.If $\dfrac{1}{2(2x+3y)}+\dfrac{12}{7(3x-2y)}=\dfrac{1}{2} $ and $\dfrac{7}{2x+3y}+\dfrac{4}{3x-2y}=2 $ then values of x and y are respectively.
2, 1
1, 2
-1, -2
-2, 1
Explanation:
Substitute from option where x=2,y=1
Therefore 2,1
35004.____river is called the "Red river" of India.
Ganga
Kosi
Damodar
Brahmaputra
35006.Identify the incorrect statement from the following in respect of seismic waves
Primary waves pass through liquid and solid
Primary waves are highly destructive
Secondary waves cannot pass through liquid
Surface waves are long waves
35008.Tea gardens over small mounds of this region is called as "Bheels"
Brahmaputra valley of Assam
Surma valley of Assam
Western Ghats of Tamil Nadu
Western Ghats of Kerala
35010.In which of the following option, the Indian states are arranged in descending order based on their size of population?
