15. At a football match, 10 men bought either a pie or a cup of coffee. A pie costs 60p and a coffee costs 50p. The total
amount spent on pies and cups of coffee was £5.80. How many
of each must have been bought?

8 pies and 2 coffees must have been bought.

Step-by-step explanation:

Given that:

10 men bought either a pie or a cup of coffee.

Cost per pie = 60p

Cost per coffee = 50p

Total amount spent = £5.80 * 100 = 580p

Let,

x be the number of pies

y be the number of coffees

According to given statement;

x+y = 10     Eqn 1

60x+50y=580    Eqn 2

Multiplying Eqn 1 by 50

50(x+y=10)

50x+50y=500      Eqn 3

Subtracting Eqn 2 from Eqn 3

(60x+50y)-(50x+50y) = 580-500

60x+50y-50x-50y=80

10x=80

Dividing both sides by 10

Putting x=8 in Eqn 1

8+y=10

y=10-8

y=2

Hence,

8 pies and 2 coffees must have been bought.

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