D a rectangle because it has four sides easy for abcd
Answer: C.
Step-by-step explanation: I used m.athway
Total number of people is 55
<u>Step-by-step explanation:</u>
Step 1:
Given ratio between boys and girls is 4:1. Let number of girls be x, so number of boys = 33 + x
⇒ 4x + x = x + 33 + x
⇒ 5x = 33 + 2x
⇒ 3x = 33
⇒ x = 11
Step 2:
Find total number of people.
33 + 2x = 33 + 22 = 55
Answer:
7y + 5z + 10
Step-by-step explanation:
2y + 7z - 2z + 4y + 8 + y + 2
Like terms are terms that have the same variable part.
2y, 4y, y are like terms (remember that y is the same as 1y when you add)
7z, -2z are like terms
8, 2 are like terms
2y + 7z - 2z + 4y + 8 + y + 2 =
= 2y + 4y + y + 7z - 2z + 8 + 2
= 7y + 5z + 10
Given:
n = 27, sample size
df = n-1 = 26, degrees of freedom
xb = 11.8, sample mean
s = 2.3, sample standard deviation.
Because population statistics are not known, we should use the Student's t-distribution.
At 99% confidence interval, the t-value = 2.779 (from tables).
The confidence interval is
11.8 +/- 2.779*(2.3/√(27)) = 11.8 +/- 1.23 = (10.57, 13.03)
Answer: (10.6, 13.0) to the nearest tenth
