In a class 40% of the students enrolled for Math and 70% enrolled for

Question

In a class 40% of the students enrolled for Math and 70% enrolled for Economics. If 15% of the students enrolled for both Math and Economics, what % of the students of the class did not enroll for either of the two subjects?

A. 0%
B. 5%
C. 15%
D. 25%
E. 35%

A. 0%
B. 5%
C. 15%
D. 25%
E. 35%

tbhauer · Answer

Consider enrollment for math and economics to be exclusive.
40%+70%=110%
If 15% enrolled for both classes, that number can be subtracted from the original sum:
110%-15%=95%
The 5% remaining would be those students who did not enroll for either class.
Ans=B

sashiim20 · Answer

Let total number of students be = 100

Students enrolled for Math = 40% of 100 = 40

Students enrolled for Economics = 70% of 100 = 70

Students enrolled for both Math and Economics =15% of 100 = 15

Let the students of the class did not enroll for either of the two subjects be = x

Total = Math + Economics - Both + Neither

100 = 40 + 70 - 15 + x

100 = 110 - 15 + x

100 = 95 + x

x = 100 - 95 = 5

Therefore the students of the class did not enroll for either of the two subjects = 5%

Answer B

ScottTargetTestPrep · Answer

Let’s assume there are 100 students. Letting N = the number of students not enrolled in either of the two subjects, we can then create the equation:

100 = 40 + 70 - 15 + N

100 = 95 + N

5 = N

Thus, we have 5/100, or 5%, of the students that did not enroll in either of the two subjects.

Answer: B

Zabihullahdalil · Answer

- Suppose, 280 is the actual number of all enrolled students.
- Number of students to be appear for Mathematics is 40% of 280 i.e. 0.4*280= 112
- Number of students to be appear for Economics is 70% of 280 i.e. 0.7*280= 196
- Number of students to be appear for both the subjects is 15% of 280 i.e 0.15*280 = 42, these students appear twice that’s why should be counted only once, thus;
- The actual number of students appearing for either of the two subjects = 112+196-42= 266
- Number of students who didn’t choose either of the two subjects = 280-266 = 14
- Percentage of students who didn’t choose either of the two subjects = (14/280)*100 = 5%

Note: 280 is the LCM of 40 & 70

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In a class 40% of the students enrolled for Math and 70% enrolled for

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