Question

The table below shows the high temperature, in degrees Fahrenheit, each day in Fairbanks, Alaska, during a week in January. Day: Sunday High temp: -8 Day: Monday High temp: 2 Day: Tuesday High temp: -6 Day:Wednesday High temp: -3 Day Thursday High temp: 4 Day: Friday High temp:5 Day Saturday High temp:-1The following sunday, Erin recorderd the High tenperature and then calculated the mean high temperature, which she found was -1.5 F. What was the temperature on Sunday?

Answer 1

Let y be the temperature

mean =-1.5

n=8

substitute in the above

`-1.5=(-8+2+(-6)+(-3)+4+5+(-1)+y)/(8)`
`-1.5=(-7+y)/(8)`

Multiply both-side of the equation by 8

`-1.5(8)=-7+y`
`-12=-7+y`

Add 7 to both-side of the equation

`-12+7=y`
`-5=y`
`y=-5`