OFFER A is cheaper.
Step-by-step explanation:
Given,
OFFER A
Pack of 5
£2.75
Pay for 3 packs get 1 free
And
OFFER A
Pack of 5
£2.75
Pay for 3 packs get 1 free
To find which offer is cheaper.
<u>For OFFER A</u>
For 4 Packets he needs to pay £2.75
He needs to buy 40 batteries.
He needs to buy 40÷(4×5) = 2 packets.
Total cost = £2.75
×2 = £5.5
<u>For OFFER B</u>
For 4 Packets he needs to pay £2.52
He needs to buy 40 batteries.
He needs to buy 10 packets.
After discount he has to pay = £2.52
-(£2.52
×
) = £1.68
Total cost = £1.68×10 = £16.8
Hence,
OFFER A is cheaper.
Answer:

Step-by-step explanation:


Subtract 9 from both sides:


Add 6x to both sides:


Divide both sides by -4:


Vertex = (1,4)
Axis of symmetry is x = 1, (1,0) or just 1
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Answer:
−28−6^2x4
Step-by-step explanation:
The expected length of code for one encoded symbol is

where
is the probability of picking the letter
, and
is the length of code needed to encode
.
is given to us, and we have

so that we expect a contribution of

bits to the code per encoded letter. For a string of length
, we would then expect
.
By definition of variance, we have
![\mathrm{Var}[L]=E\left[(L-E[L])^2\right]=E[L^2]-E[L]^2](https://tex.z-dn.net/?f=%5Cmathrm%7BVar%7D%5BL%5D%3DE%5Cleft%5B%28L-E%5BL%5D%29%5E2%5Cright%5D%3DE%5BL%5E2%5D-E%5BL%5D%5E2)
For a string consisting of one letter, we have

so that the variance for the length such a string is

"squared" bits per encoded letter. For a string of length
, we would get
.