Answer:
Step-by-step explanation:
The system of equations given are:
5x - y + z = -6 ------------- i
2x + 7y + 3z = 8 ---------- ii
x + 2z = 6 ----------------- iii
Let us deal with equation i and ii first since they have 3 variables x, y and z;
5x - y + z = -6 x 7
2x + 7y + 3z = 8 x 1
35x - 7y + 7z = -42 ---- iv
2x + 7y + 3z = 8 ---- v
Add equation iv and v;
37x + 10z = -34 ------vi
So, let us solve equation vi and iii:
x + 2z = 6 - ---------- iii x 10
37x + 10z = -34 --- iv x 2
10x + 20z = 60 vi
74x + 20z = -68 vii
Subtract vi - vii;
-64x = 128
x = -2
So; put x = -2 into iii;
x + 2z = 6
-2 + 2z = 6
2z = 6 + 2 = 8
z = 4
Put x = -2 and z = 4 into equation i;
5(-2) - y + 4 = - 6
-10 -y +4 = -6
-6 - y = -6
-y = 0
y = 0
7.43: Let
denote the random variable for height and
for the sample mean. Then if
is the mean of
So the probability that the difference between the sample and population means does not exceed 0.5 inch is

per the empirical or 68/95/99.7 rule.
7.44: For a sample of size <em>n</em>, the sample standard deviation would be
. We want to find <em>n</em> such that

Comparing to the equation from the previous part, this means we would need

so a sample of at least 157 men would be sufficient.
Answer:
1.25
Step-by-step explanation:
-3/4+2=1.25
Answer:
So, when we solve for x we see that we can make 16 cookies using 1 cup of sugar. Then, yes, as you suggested we could divide 30 cookies by this ratio to see that we need less than 2 cups of sugar to make 30 cookies: And, as you said, this value is less than 2 cups, the value under Quantity B. Good job! I hope this helps :)
Step-by-step explanation: