Answer:
a) M =82
Step-by-step explanation:
Let´s study this as a Normal distribution.
As we know in a normal distribution the z score is = (X-μ)/(sd/sqrt(n))
where
X = mean for the taken sample = What we want to know in this problem
μ = Total population mean =80
sd= standard deviation= 12
n = sample size=9
So in this case z=( X-80)/(12/sqr(9))= (X-80)/4
also we know that the effect size taken by the machine is 0.5, which is the same as the z-score
so...
0.5 = (X-80)/4 => 0.5*4 = X-80
2+80 = X
X = 82
<span>When you add fractions, the denominators must be the same, so you may have to generate equivalent fractions by using the lowest common multiple of all the denominators. For subtraction of fractions, you use the same method. When multiplying fractions, you can only multiply the numerators together, and the denominators together. </span>
Answer:
4356
use a calculator
Answer:
r = 3 and t=5, then d = 8 is not true.
Step-by-step explanation:
Because 8 is not equal to 3*5
(b)+(b+45)=215
b = # of boys
there are 45 more girls than boys and 215 students total.
minus 45 on both sides leaving you with
(b)+(b)=170
combine like terms leaving you with
2b=170
divide both sides by 2
b=85
there were 85 boys
85+45=130
(the 45 for the # of girls more than boys)
there were 130 girls.
