TCS
Company
Numerical Ability
Sequence and Series
What is the sum of all even integers between 99 and 301?
Option
A. 40000
B. 20000
C. 40400
D. 20200
Read Solution (Total 13)
-
- D. 20200
Even integers between 99 and 301 are 100,102,104,....,300
To find total even numbers n , 300=100+(n-1)2, n=101
Sum of all numbers=(101/2)[2*100+ (101-1)2]
=10100+10100 =20200 - 10 years agoHelpfull: Yes(28) No(0)
- 20200
100+102+104+....298+300 = (2+4+6+...298+300) - (2+4+6+...+96+98)
=2*(1+2+3+...+150) - 2*(1+2+3+...49)
=150*151 - 49*50
=20200 - 10 years agoHelpfull: Yes(9) No(1)
- ACCORDING TO A.P
A=100 L=300 n=? D=2
300=100+(n-1)2 (Tn=a+(n-1)d)
200=(n-1)2
n=101
so, Sn=(101/2)*(100+300) (Sn=(n/2)*(a+l))
=40400/2
=20200
answer= 20200 - 10 years agoHelpfull: Yes(7) No(1)
- ans:D
frst & last even nums between 99 and 301 are 100 & 300 respectivly..
in Arthmtic progression,
no.of even integers n= [(last num- frst term)/commn diffrnce]+1
n=[(300-100)/2]+1=101
sum=n/2[frst term+last term]
sum=101/2[100+300]=20200 - 10 years agoHelpfull: Yes(1) No(0)
- yes D. is the rght ans
- 10 years agoHelpfull: Yes(0) No(0)
- 100+102+104+..........+300
tn=300,a=100,d=2
tn=a+(n=1)d,solving it we get n=101
sn=n/2(2a+(n-1)d),solving it ans is 20200 - 10 years agoHelpfull: Yes(0) No(0)
- sum = 100+102+........+300
it is an A.P where d=2 , n=101[(300-100)/2 + 1 =101]
sum=101/2[2x100 + (101-1)x2]
=20200
option d - 10 years agoHelpfull: Yes(0) No(0)
- n/2[a+l] formula n=101 a=100 l=300
ans 20200 - 10 years agoHelpfull: Yes(0) No(0)
- total elements are 100
1st term is 100 and last term is 300
then the total sum of the even elements is
100(100+300)/2=20000 - 10 years agoHelpfull: Yes(0) No(0)
- ans is 20200
- 10 years agoHelpfull: Yes(0) No(0)
- ans is 20200
- 10 years agoHelpfull: Yes(0) No(0)
- 300=100+(n-1)2
200/2=n-1
101=n
S=((100+300)*101)/2
s=20200
so option d is correct - 10 years agoHelpfull: Yes(0) No(0)
- answer id D
- 10 years agoHelpfull: Yes(0) No(0)
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