In a middle school 5th grade class there are 5 girls for every 4 boys. all together the class has 27 students. How many boys are in the class?
4/9 = b/27
9b = 108
b = 12
12
4/9=b/27
9b=108
108/9=
12 boys
To determine the number of boys in the class, we first need to find the ratio between girls and boys. Given that there are 5 girls for every 4 boys, the total ratio of girls to boys is 5:4.
Next, we can represent the number of students in terms of this ratio. Let's assume the total number of students is x. According to the given information, there are 5/9 (5 girls out of 9 total parts) * x girls and 4/9 (4 boys out of 9 total parts) * x boys in the class.
Since the total number of students is given as 27, we can set up the equation:
(5/9)x + (4/9)x = 27
To solve this equation, we first simplify by finding a common denominator:
(5x + 4x) / 9 = 27
Combining like terms:
9x / 9 = 27
We can then solve for x by multiplying both sides of the equation by 9:
9x = 27 * 9
Simplifying the right side:
9x = 243
Finally, solve for x by dividing both sides of the equation by 9:
x = 27
So, there are 27 students in the class. To find the number of boys, we can substitute x back into the equation:
(4/9) * 27 = 12
Therefore, there are 12 boys in the class.