Answer:
(115.2642, 222.7358).
Step-by-step explanation:
Given data:
type A: n_1=60, xbar_1=1827, s_1=168
type B: n_2=180, xbar_2=1658, s_2=225
n_1 = sample size 1, n_2= sample size 2
xbar_1, xbar_2 are mean life of sample 1 and 2 respectively. Similarly, s_1 and s_2 are standard deviation of 1,2.
a=0.05, |Z(0.025)|=1.96 (from the standard normal table)
So 95% CI is
(xbar_1 -xbar_2) ± Z×√[s1^2/n1 + s2^2/n2]
=(1827-1658) ± 1.96×sqrt(168^2/60 + 225^2/180)
= (115.2642, 222.7358).
We need to get x alone, to do that we add 1 to both sides to cancel out the -1 on the right.
-4 = x -1
+1 +1
-3=x
This means x is equal to -3. Hope this helps!
Try this option:
if x+y=-9 is I (one)
and x+2y=-25 is II (two), then
if II-I, then (x+2y)-(x+y)=-25+9 ⇔ y=-16.
Answer:
75c-180
420 for 8 customers
Step-by-step explanation:
Her tools cost her 180
-180
she makes 75 per customer
75c
She will make
75c-180
She gets 8 customers
75(8)-180
600-180
420