Respuesta :
Answer:
20d + 30d = 50d
Step-by-step explanation:
We know the variable d represents the number of days.
He practices piano 20 minutes per day; this gives us the expression 20d.
He practices guitar 30 minutes per day; this gives us the expression 30d.
Together, this gives us
20d + 30d; combining like terms gives us
50d.
The expression that represents the number of minutes Caleb spends practicing instruments after d days is 50d
The rates are given as:
[tex]Piano= 20\ minutes[/tex]
[tex]Guitar= 30\ minutes[/tex]
The total number of minutes spent on practicing instruments daily is:
[tex]Daily = Piano + Guitar[/tex]
So, we have:
[tex]Daily = 20\ minutes + 30\ minutes[/tex]
[tex]Daily = 50\ minutes[/tex]
For d days, the total number of minutes is:
[tex]Total = Daily \times d[/tex]
[tex]Total = 50\times d[/tex]
[tex]Total = 50d[/tex]
Hence, the expression is 50d
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