Answer:
11/19
Step-by-step explanation:
Firstly, we need to know the total number of instructors. This is equal to 7+5+4+3 = 19 instructors.
The probability of selecting a science instructor is 4/19
The probability of selecting a math instructor is 7/19
The probability of selecting either a science or a maths instructor is 4/19 + 7/19 = 11/19
To determine the number of days that an employee work in a week, we simply use dimensional analysis and multiplying the number of works per week with the number of weeks in total for a year. That is,
employee works = (5 days per week)(49 weeks per year)
=245 days
1 = 1 x 1
1 factors
2 = 1 x 2
2 factors
3 = 1 x 3
2 factors
4 = 1 x 4
4 = 2 x 2
3 factors
5 = 1 x 5
2 factors
6 = 1 x 6
6 = 2 x 3
4 factors
7 = 1 x 7
2 factors
8 = 1 x 8
8 = 2 x 4
4 factors
9 = 1 x 9
9 = 3 x 3
3 factors
10 = 1 x 10
10 = 2 x 5
4 factors
11 = 1 x 11
2 factors
12 = 1 x 12
12 = 2 x 6
12 = 3 x 4
6 factors
13 = 1 x 13
2 factors
14 = 1 x 14
14 = 2 x 7
4 factors
15 = 1 x 15
15 = 3 x 5
4 factors
16 = 1 x 16
16 = 2 x 8
16 = 4 x 4
5 factors
17 = 1 x 17
2 factors
18 = 1 x 18
18 = 2 x 9
18 = 3 x 6
6 factors
19 = 1 x 19
2 factors
20 = 1x 20
20 = 2 x10
20 = 4 x 5
6 factors
So they are 6, 8, 10, 14 and 15 on the number line
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
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