Answer:
At least 16 calls must be made.
Step-by-step explanation:
It is given that Joes electric made 19 customer calls last week and 25 this week.
Let x calls be made next week in a order to maintain an average of at least 20 calls per week for three week period.
[tex]Average=\dfrac{\text{Sum of observations}}{\text{Number of observations}}[/tex]
[tex]Average=\dfrac{19+25+x}{3}[/tex]
[tex]Average=\dfrac{44+x}{3}[/tex]
Average at least 20.
[tex]Average\geq 20[/tex]
[tex]\dfrac{44+x}{3}\geq 20[/tex]
[tex]44+x\geq 60[/tex]
[tex]x\geq 60-44[/tex]
[tex]x\geq 16[/tex]
Hence, at least 16 calls must be made.
