Need to be done asap

to make one cheese sandwich, tina uses one bread roll and two cheese slices.
pack of 15 bread rolls
£1.91
pack of 20 cheese slices
£2.23
she is going to buy enough packs to
have exactly twice as many cheese slices as bread rolls
make more than 100 cheese sandwiches.
work out the least amount she can spend.

i think the answer is seven, for if i'm being useless °ω°

step-by-step explanation:

step-by-step explanation:

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step-by-step explanation:

part a. the differences are decreasing, so we know the sequence is not arithmetic. the ratios are constant (=3/4), so we know the sequence is geometric.

part b. from part a, we know the common ratio is 3/4, so each term is 3/4 of the one before. the initial term is the number of gallons at h=1.

g[h] = (3/4)·g[h-1]

g[1] = 384 . . . . initial value required for a recursive definition

part c. the general formula for a geometric sequence is

a[n] = a[1]·r^(n-1)

we have a[1] = 384, r = 3/4, and the term number given by h. the formula that follows is

g[h] = 384·(3/4)^(h-1)

part d. filling in the value and doing the arithmetic, we have

g[12] = 384·(3/4)^11 ≈ 384·0.042235136 ≈ 16.2183 . . gallons

part e. each gallon is 4 quarts, so

16.2183 gal × 4 qt/gal = 64.8732 qt