One cookie costs $0.20 and one drink costs $1.65
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Let D represent the cost of a drink and C represent the cost of a cookie.
Set up equations based on given details.
From Juan's purchase:
From Keisha's purchase:
Subtract the second equation from the first to find the cost of one cookie:
- D + 2C - (D + C) = $2.05 - $1.85
- C = $0.20 (cost of one cookie)
Substitute the value of C into Keisha's equation to find D:
- D + $0.20 = $1.85
- D = $1.85 - $0.20
- D = $1.65 (cost of one drink)
