Answer: It costs $5.52 to Sam to buy 12 stamps.
Step-by-step explanation:
Given: Sam paid $8.28 for 18 stamps.
Thus, the cost of 18 stamps = $8.28
Then the cost of 1 stamp=
Thus, the cost of 1 stamp=$0.46
With the same rate , the cost of 12 stamps=
Therefore, the cost of 12 stamps= $5.52
hence, it costs $5.52 to Sam to buy 12 stamps.
Replace the second equation y=3x+4 into the first one:
2(3x+4)+5x=30
Now solve for x:
6x+8+5x=30
11x=30-8
11x=22
x=22/11
x=2
Finally, replace x=2 into y=3x+4
y=3*2+4
y=6+4 = 10
So the anwer is x=2, y=10
Answer:
1941.2 feet
Step-by-step explanation:

B is correct the devotion is only 2 compared to 4.
A is wrong because variate A has higher trees then variate B
C is wrong because deviation for A is 4 compared to 2 ( opposite of B)
D is wrong because 4th one is 10 for A and 13 for B. 10 is not greater than 13