Serenity and her children went into a movie theater and she’s bought $77.75 worth of drinks and pretzels. each drink costs $5.50 and each pretzel costs $3.25. she bought 3 more drinks than pretzels. determine the number of drinks and the number of pretzels that serenity bought.

The number of drinks bought is 10 and number of pretzels bought is 7

Let "d" be the number of drinks bought

Let "p" be the number of pretzels that Serenity bought

Cost of one drink = $5.50

Cost of one Pretzel = $3.25

Given that she’s bought $77.75 worth of drinks and pretzels

So we can frame a equation as:

number of drinks bought x Cost of one drink + number of pretzels bought x Cost of one Pretzel = 77.75

5.5d + 3.25p = 77.75 ----- eqn 1

Given that She bought 3 more drinks than pretzels

Number of drinks bought = 3 + number of pretzels bought

d = 3 + p

d - p = 3 --- eqn 2

Let us solve eqn 1 and eqn 2 to find values of "d" and "t"

Multiply eqn 2 by 3.25

3.25d - 3.25p = 9.75 ---- eqn 3

Add eqn 1 and eqn 3

5.5d + 3.25p = 77.75

3.25d - 3.25p = 9.75

(+) ---------------------------

8.75d = 87.5

d = 10

Substitute d = 10 in eqn 2

10 - p = 3

p = 7

Thus the number of drinks bought is 10 and number of pretzels bought is 7

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