Answer:
B
Step-by-step explanation:
First calculate BD using sine ratio in Δ BCD and the exact value
sin60° = 
, thus
sin60° = 
= 
= 
= ( cross- multiply )
2BD = 12
( divide both sides by 2 )
BD = 6
-----------------------------------------------------------
Calculate AD using the tangent ratio in Δ ABD and the exact value
tan30° = 
, thus
tan30° = 
= 
= 
= ( cross- multiply )
AD = 6 ( divide both sides by )
AD = 6 → B
The answer is the first one in the options
Answer:
53
Step-by-step explanation:
86 = 2x - 20
<u>+20 +20</u>
<u>106 </u>= <u>2x</u>
2 2
53 = x
Answer:
Mr Blake's science class
Step-by-step explanation:
The standard deviation is a measure of variation.
It tells us how far each of the data set in the distribution are far from the mean of the distribution.
The average score of students in Mr. Blake's science class was 73 with a standard deviation of 11, while the average score of students in Mrs. Arnold's class was 75 with a standard deviation of 10.
Since 11>10, Mr Blake's science class is more variable than Mrs. Arnold's class.
