In a certain high school, 20 percent of the students in the sophomore

Question

Competition Mode Question

In a certain high school, 20 percent of the students in the sophomore class have obtained a driver's license, and half of those students took a driver's education class. Of the sophomores without a license, 70 percent have taken a driver's education class. What percentage of the class has not taken a driver's education class?

A. 66
B. 50
C. 44
D. 36
E. 34

A. 66
B. 50
C. 44
D. 36
E. 34

SP21 · Answer

10+ (30/100*80) 
10+ 24 
=34

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eakabuah · Answer

Let total number of Sophomore class be 100.
The portion of the class who have Driver's License, A, = 20% = 20
The portion of the class without a Driver's License, B, = 80% = 80

We know from the question stem that half of the class with Driver's License took Driver Education Classes. This implies half of A did not take Driver's Education Class.
Hence number out of A, who do not have Driver's Education = 0.5*20 = 10

We also know from the question stem that 70% of those without Driver's License, B, took Driver Education Classes, implying 30% of B did not take the class.
Number out of A without the class = 0.3*80 = 24
Total without the class = 24+10 = 34
Hence 34% did not take the Driver Education Class.

Option E is the answer in my view.

madgmat2019 · Answer

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joohwangie · Answer

In a certain high school, 20 percent of the students in the sophomore class have obtained a driver's license, and half of those students took a driver's education class. Of the sophomores without a license, 70 percent have taken a driver's education class. What percentage of the class has not taken a driver's education class?

A. 66
B. 50
C. 44
D. 36
E. 34

assume there are 100 sophomore
20% of sophomore have driver's license: 20
half of those took driver's class: 10
of sophomore w/o license, 70% taken driver's class: .7x(100-20): 56
what percentage of the class(sophomore) has not taken a driver's class: 100-10-56=34

Therefore, E

unraveled · Answer

In a certain high school, 20 percent of the students in the sophomore class have obtained a driver's license, and half of those students took a driver's education class. Of the sophomores without a license, 70 percent have taken a driver's education class. What percentage of the class has not taken a driver's education class?

A. 66
B. 50
C. 44
D. 36
E. 34

A. 66
B. 50
C. 44
D. 36
E. 34

Half of students with drier's license have taken driver's education class i.e 20%/2 = 10%
Since 80% students are without a license which includes 70% who have taken driver's education class and remaining without it, percentage of students without driver's education class is 30% * 80% = 24%

Hence total students without driver's education class = 24 + 10 = 34%

IMO Answer E.

exc4libur · Answer

............drivers:......not:
class…..0.5(1/5)....0.7(4/5)
not…....0.5(1/5)......0.3(4/5)
total.......1/5........4/5

not: 0.5(1/5)+0.3(4/5)=34/100

Answer (E)

Archit3110 · Answer

solve using 2x2 matrix
-----DL--NDL---Total
Class-10--56-----66
nclas--10--24---- 34 
total--20---80---100

IMO E; 34

In a certain high school, 20 percent of the students in the sophomore class have obtained a driver's license, and half of those students took a driver's education class. Of the sophomores without a license, 70 percent have taken a driver's education class. What percentage of the class has not taken a driver's education class?

A. 66
B. 50
C. 44
D. 36
E. 34

A. 66
B. 50
C. 44
D. 36
E. 34

lacktutor · Answer

Let 100 be the number of students in the sophomore class. 
—> 20% of them have a driver’s license: 
—> 10 of them took driver’s education class 
—> the other 10 students didn’t take driver’s education class

80 students don’t have driver’s license: 
—> 80*70%= 80*70/100=56 students have taken the driver’s education class. 
—> 80– 56= 24 students haven’t taken that class. 
In total, there are 10+24=34 students have not taken the driver’s education class
—> that means 34 % of the class have not taken the driver’s education class.

The answer is E

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ScottTargetTestPrep · Answer

We can let n = the total number of students in the sophomore class. We know that 0.2n have a license and 0.8n do not have a license.

0.2n * 0.5 = 0.1n took a driver’s education class and have a licence and

0.8n * 0.7 = 0.56n took a driver’s education class but do not have a licence.

Thus, 0.1n + 0.56n = 0.66n students took a driver’s education class, which means 0.34n, or 34% of the students, have not taken a driver’s education class.

Answer: E

bumpbot · Answer

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In a certain high school, 20 percent of the students in the sophomore

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