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Percentage
A survey of n people in the town of Eros found that 50% of them preferred Brand A. Another surveyof 100 people in the town of Angie found that 60% preferred Brand A. In total, 55% of all the people surveyed together preferred Brand A. What is the total number of people surveyed?
(A)50
(B)100
(C)150
(D)200
(E)250
Read Solution (Total 7)
-
- 50% of n people from Eros prefer brand A.
50% of n is 50/100 x n = n/2.
60% of 100 people from Angie prefer brand A.
60% of 100 is 60/100 x 100 = 60.
Of the total n+ 100 people surveyed, n/2 + 60 prefer brand A.
Given that this is 55%,
we have
(n/2+60)/(n+100) x100 =55
Solving the equation
(n/2+60)/(n+100) x100= 55
(n/2+60) = 55/100x(n+100)
(n/2+60) = 11/20n+55
0 = 11n /20 –n/2+55-60
Now subtracting n/2 and 60 from both sides
0=n/20-5
Adding 5 on both sides
5=n/20
n=100
Hence, the total number of people surveyed is
n+ 100 = 100 + 100
= 200.
The answer is (D).
- 12 years agoHelpfull: Yes(18) No(5)
- Total no of people surveyed is (100+n)
In town eros 0.5n people preferred brand A
In town angie 60 people preferred brand A
Now total no of people who preferred brand A is given as (0.5n+60)
which is also equal to 55% of total surveyed people ==> 0.55(100+n)
i.e (0.5n+60)=0.55(100+n)
0.05n=5
n=5/0.05
n=100
therefore total no of people surveyed is (100+100)=200 (option D) - 12 years agoHelpfull: Yes(8) No(0)
- BRAND A
1. 50%(n)
2. 60%(100)=60
3. 55% overall
if n=100
then (50+60)/2=55% - 12 years agoHelpfull: Yes(2) No(9)
- ans) B
no.of people of Eros preffered brand A= n/2
no.of people of Angie preffered brand A= 60%of 100= 60
hence total no.of people of preffered brand A = n/2+60
n/2+60 = 55% of (n+100)
by computing above eqn n=100
hence total no.of people surveyed= n+100 =100+100= 200 - 12 years agoHelpfull: Yes(2) No(0)
- ans:100
n(50/100)+100(60/100)=55/100(n+100)
==>n=100 - 12 years agoHelpfull: Yes(1) No(5)
- given 55% of surveyed people preffered brand A.
i,e (50%+60%)/2=55%.
so n must be 100 to get 50%.
so B is right ans - 12 years agoHelpfull: Yes(1) No(2)
- 1. 50%(n)
2. 60%(100)=60
3. 55% overall
if n=100
then (50+60)/2=55%
so 100+100=200. - 12 years agoHelpfull: Yes(1) No(0)
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