Final answer:
To solve this problem, assume the number of girls as 'x' and set up equations based on the given information. Solve the equations to find the number of girls and boys in the class.
Step-by-step explanation:
To solve this problem, we can use algebraic equations. Let's assume the number of girls in the class to be 'x'. According to the given information, the number of boys will be 'x+1'.
One third of the boys love pizza, which is (1/3)(x+1) = (x+1)/3.
Three fourths of the girls love pizza, which is (3/4)x. Therefore, the total number of students who love pizza is (x+1)/3 + (3/4)x = 9.
To solve this equation, we can multiply the whole equation by the least common denominator, which is 12. This gives us 4(x+1) + 9x = 108. Simplifying, we get 13x + 4 = 108. Subtracting 4 from both sides, we have 13x = 104. Dividing both sides by 13, we find that x = 8.
Therefore, there are 8 girls and 8+1 = 9 boys in the class.