Answer:
b=32
Step-by-step explanation:
Answer:
C. 40 cm
Step-by-step explanation:
length of side of square = s
perimeter = s + s + s + s = 4s
We use the formula P = 4s
P = 4 * 10 cm
P = 40 cm
Answer: The perimeter is 40 cm.
Notice that the perimeter is a sum of lengths, so its units are linear units such as cm, inches, feet, a unit of length.
An area has square units such as cm^2, in.^2, ft^2, etc.
Answer: How many boys want to go skating
Step-by-step explanation: sorry if wrong but if you add 50 and 45 and 60 you get 155 that is not 210 so 2
One orange costs 0.45 so a lemon costs 55 cents more than one orange
Answer:
A) Population standard deviation is known.
B) Option 3
H0: μ =520,
H1: μ ≠ 520
z > 1.96 or z < -1.96
Step-by-step explanation:
A) The normal distribution should be used for the sample mean because the population standard deviation is known. Usually, when the standard deviation is unknown we don't use normal distribution except there is an underlying normal approximation.
B) Null Hypothesis:H0: μ =520,
Alternative hypothesis H1: μ ≠ 520
At 5% level of significance, from standard tables, we will reject H0 if;
The test statistic; z > 1.96 or z < -1.96