Question

1. two customers purchased coffee and doughnuts at a coffee shop. each cup of coffee costs the same amount, and each doughnut costs the same amount. - the first customer paid $4.90 for 1 cup of coffee and 2 doughnuts. - the second customer paid $8.60 for 2 cups of coffee and 3 doughnuts. what is the cost of 1 cup of coffee? $2.50 $1.20 $4.90 $3.70 clear all

Explanation:

Step1: Define variables

Let $c$ = cost of 1 coffee, $d$ = cost of 1 doughnut.

Step2: Set up equations

First customer: $c + 2d = 4.90$
Second customer: $2c + 3d = 8.60$

Step3: Eliminate $d$ variable

Multiply first equation by 3: $3c + 6d = 14.70$
Multiply second equation by 2: $4c + 6d = 17.20$
Subtract new first equation from new second equation:
$(4c + 6d) - (3c + 6d) = 17.20 - 14.70$
$c = 2.50$

Answer:

$2.50$ (Option A. $2.50$)