Mrs. Shelton doesn't have enough marking pens for everyone in class. Every 2 students share a green pen and every 4 students share a red pen. If she has

Question

Mrs. Shelton doesn't have enough marking pens for everyone in class. Every 2 students share a green pen and every 4 students share a red pen. If she has

15 marking pens in all how many students are in Mrs. Shelton's class?

Answer 1

there is 20 kids min the class

Answer 2

To solve this problem, we can start by assigning variables to the unknown quantities. Let's call the number of students in the class "S".

According to the problem, every 2 students share a green pen. This means that the number of green pens required is equal to half the number of students in the class, or S/2.

Similarly, every 4 students share a red pen. Therefore, the number of red pens required is equal to one-fourth of the number of students in the class, or S/4.

Since Mrs. Shelton has a total of 15 marking pens, the sum of the green pens and red pens should be equal to 15:
S/2 + S/4 = 15

To solve this equation, we can multiply through by the least common denominator (4) to eliminate the fractions:
2S + S = 60

Combine like terms:
3S = 60

Divide both sides by 3 to isolate S:
S = 60/3

Simplify:
S = 20

Therefore, there are 20 students in Mrs. Shelton's class.

Answer 3

Does each student have access to one or to two marking pens?

Answer 4

What a great question! One has to begin by assuming that all students have access to both a red and a green pen. We know that the sum of the pens is 15, and that "the number of students" must be divisible by both 4 and 2. In fact, the sum of the quotients of the "number of students" divided by first 4, then 2, must equal 15. One of my students drew a nice diagram of how this can work.