40 tickets were sold for a concert, some at 75 cents and the rest at $1.25. if the total raised was $42, how many had the cheaper ticket. please i need this for an assignment​

34

Step-by-step explanation:

$1.25 = 125 cents.

$42 = 4200 cents

Tickets sold at 75 cents = x

Tickets sold at 125 cents = y

x + y = 40

75x + 125y = 4200

Multiply the first equation by 75

75x + 75y = 3000

75x + 125y = 4200

Subtract the the second equation from the first.

75x + 75y = 3000

- 75x + 125y = 4200

0 - 150y = - 1200

Divide both sides by - 150

-150y/-150 = -1200/-150

y = 8

Substitute y = 8 into the first equation

x + y = 42

x + 8 = 42

x = 42 - 8

x = 34

34 tickets were sold for 75 cents

8 tickets were sold for $1.25

let x be the money she spent so that she can earn the free t-shirt.

since, she already spent $112.49

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also, as per the statement: jennifer must spend $250 or more in order to qualify for a free t-shirt at the store.

then,

we have an inequality i.,e

subtract 112.49 from both sides we get;

therefore, $137. 51 more money does jennifer need to spend so that she can earn the free t-shirt