2/3 of miss lina's class were boys. there were between 2 and 14 boys. One day, twin girls joined the class. Now 3/5 of the students are boys. how many students are in miss lina's class now?
If there were originally b boys out of s students in the class,
b/s = 2/3
b/(s+2) = 3/5
Or,
b = 2s/3
5b = 3s+6
So,
5(2s/3) = 3s+6
10s = 9s+18
s = 18
Now you should be able to answer the question.
To solve this problem, we need to find the total number of students in Miss Lina's class. Let's go step by step:
Step 1: Identify the initial number of boys in Miss Lina's class.
We know that initially, 2/3 of the class were boys. This means that the number of boys is a multiple of 2/3 between 2 and 14.
The multiples of 2/3 between 2 and 14 are: 2/3, 4/3, 2, 8/3, 10/3, 4, 14/3, 16/3, 6, 20/3, 22/3, 8, 26/3, 28/3, 10, 32/3, 34/3, 12, and 14.
From this list, we can see that the only possible whole number of boys is 4.
Step 2: Find the initial number of students in Miss Lina's class.
Since 2/3 of the class were boys, the number of girls must be 1/3 of the total number of students.
So, to find the initial number of students, we divide the number of boys by 2/3, or multiply it by 3/2.
Initial number of students = 4 * (3/2) = 6.
Step 3: Add the twin girls to the class.
Now that the twin girls have joined the class, we need to add 2 to the total number of students.
Final number of students = Initial number of students + 2 = 6 + 2 = 8
Therefore, there are 8 students in Miss Lina's class now.