Answer:
B
Step-by-step explanation:
Standard deviation is the average distance away from the mean, thus B is correct
Let:
x = cost of senior citizen ticket
y = cost of student ticket
4x + 5y = 102
7x + 5y = 126
4x + 5y = 102
4x = 102 - 5y
x = (102 - 5y)/4
x = 102/4 - 5y/4
7x + 5y = 126
7(102/4 - 5y/4) + 5y = 126
(714/4 - 35y/4) + 5y = 126
-35y/4 + 5y = 126 - 714/4
note:
-35y/4 = -8.75y
714/4 = 178.5
-8.75y + 5y = 126 - 178.5
-3.75y = -52.5
y = -52.5/-3.75
y = 14
x = 102/4 - 5y/4
x = 102/4 - 5(14)/4
x = 8
x = cost of senior citizen ticket = $8/ea
y = cost of student ticket = $14/ea
712 is the answer of this question
Answer:
24mm
Step-by-step explanation:
since it's a similar triangle, we solve;
EH/EG=DH/DG
EH=56mm;
EG=44.8mm;
DH=35mm;
DG=X+4.
Fix them,
56/44.8=35/x+4
cross multiply
56(x+4)=35×44.8
56x+224=1,568
collect the like term
56x=1,344
divide via by 56
56x/56=1344/56
x=24mm
Check/ verify
EH/EG=DH/DG
56/44.8=35/24+4
56/44.8=35/28
CROSS MULTIPLY OVER THE EQUAL SIGN.
56×28=35×44.8
1,568=1,568
THAT'S CORRECT.
Answer:
D. The rate of change must be 20 pounds per minute.
Step-by-step explanation:
At time 0, the amount of sand is 200 lb. Time zero is when it starts, so it is also called the initial time. The initial value is 200 lb, so choices A and B are wrong.
Now look at the difference from time 0 minutes to time 1 minute. The amount of sand went from 200 lb to 220 lb. The amount of sand placed in 1 minute is 20 lb, so the rate of change is 20 lb per minute. That makes choice C wrong and choice D correct.
Answer: D. The rate of change must be 20 pounds per minute.
