<span>3n + 4 = 7
</span><span>3n = 7 - 4
3n = 3
n = 1</span>
Answer is 7
Step by step explanation
3x+159=180
3x=180-159=21
x=7
There are 200 students in the group.
To find this, you divide 70 by 0.35 (35%). This will give you 200. To check this, multiply 200 by 0.35 and you will get 70. Thus making 200 the answer.
I hope this helps!
Answer:
Step-by-step explanation:
find the attachment showing std normal curve symmetrical about y axis.
Equal probabilities on either side of the mean thus the total probability to the right of mean is 0.50
From the table we can find that
a) P(Z>2.5) = 0.5- area lying between 0 and 2.5
= 0.5-0.4938 =0.0062
b) P(1.2<z<2.2) = F(2.2)-F(1.2)
= 0.9861-0.3849
=0.6012