The addition of a negative is basically the same as subtraction.
Since your adding -35 to 90, your just taking away 35 from 90.
You would set up the problem like this:
90 + – 35
Or you could write it out like this:
90 – 35
Either way, 90 + – 35 = 55
Mean of the 5 is the average
lets solve for what score gets 80
and lets say last score is x
so
(sum of scores)/4=80
(62+75+90+x)/4=80
(227+x)/4=80
times 4 both sides
227+x=320
minus 227 from both sides
x=93
yo need a 93
good luck
Noah , because the ratio of powder to water is a good amount
The area of a trapezoid = 0.5h(a + b) where a and b are the lengths of the parallel sides
so here we have 0.5(8)(a + 12) = 144
solve for a
4(a + 12) = 144
4a + 48 = 144
4a = 96
a = 96/4 = 24