Answer:
1.46
Step-by-step explanation:
First find the the mean score before he made a 90.

Now add the score of 90 and calculate.

Subtract the two scores.

His mean test score increased by 1.46.
Answer: -x because its more than one zero
Step-by-step explanation:
I would use elimination. I would multiply 4x+3y=2 by 3 so the it becomes 12x+9y=6, and I would multiply the bottom equation by 4 so that it becomes 12x+8y=4. Because I am using elimination I have to get rid of one variable, I chose to get rid of X hence that the coefficient of X in each equation is now 12. i simply subtract both equations and get y by itself. y=2. I plug in Y to find x in either of the original equations, where I get x=-1. To check my work substitute the values of x and y in the other equation. 4(-1)+3(2)=2 -------> 2=2
Answer:
3:5 = 30:50 because it is ratio 3 x 10 = 30 5 x 10 = 50
Take 30 and divide it by .2
You will get 150 books