Answer:
£70.00
Step-by-step explanation:
You basically want to find what she spent in total, then subtract the amount she spent on ingredients. 
50 glasses of lemonade at £2.10 each would be £105. (50*2.1)
Subtract the cost of ingredients, which is £35, with the total she made, £105, to get £70 (105-35)
 
        
             
        
        
        
Answer:
21
Step-by-step explanation: 
20 x 10 = 200 so 20 students sleep for 9 hours
that leaves 10
since 10 is half of 20, half of 2 is 1 so that last 10 = 1 student,
making 21 students
 
        
             
        
        
        
Answer:
Kindly check explanation
Step-by-step explanation:
 
Given the data :
Technician __Shutdown 
Taylor, T___4 
Rousche, R _ 3
Hurley, H__ 3 
Huang, Hu___2
Gupta, ___ 5
The Numbe of samples of 2 possible from the 5 technicians :
We use combination :
nCr = n! ÷ (n-r)!r!
5C2 = 5!(3!)2!
5C2 = (5*4)/2 = 10
POSSIBLE COMBINATIONS :
TR, TH, THu, TG, RH, RHu, RG , HHu, HG, HuG
Sample means :
TR = (4+3)/2 = 3.5
TH = (4+3)/2 = 3.5 
THu = (4+2) = 6/2 = 3
TG = (4 + 5) = 9/2 = 4.5
RH = (3+3) = 6/2 = 3
RHu = (3+2) /2 = 2.5
RG = (3 + 5) = 8/2 = 4
HHu = (3+2) = 2.5 
HG = (3+5) = 8/2 = 4 
HuG = (2+5) / 2 = 3.5
Mean of sample mean (3.5+3.5+3+4.5+3+2.5+4+2.5+4+3.5) / 10 = 3.4
Population mean :
(4 + 3 + 3 + 2 + 5) / 5 = 17 /5 = 3.4
Population Mean and mean of sample means are the same. 
This distribution should be approximately normal. 
 
        
             
        
        
        
no solution, since the graph two parallel lines with no intersect