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).
D = 25 ft is the length of a shadow. L - the length of a tree.
Two angles are 85° and 65° and the third is 180° - ( 65° + 85° ) =
= 180° - 150° = 30°.
We will use the Sine Law:
25 / sin 30° = L / sin 65°
25 / 0.5 = L / 0.9063
25 * 0.9063 = 0.5 L
22.6577 = 0.5 L
L = 22.6577 : 0.5
L = 45.3 ft.
Answer: the approximate length of the tree is 45.3 ft.
Answer:
25 gallons
Step-by-step explanation:
Assuming miles-per-gallon is a constant, the amount of gas is proportional to the miles driven:
gallons/(500 mi) = (13 gal)/(260 mi)
gallons = (500 mi)/(260 mi)(13 gal) . . . . multiply by 500 mi
gallons = 25 gal . . . . do the arithmetic
The van will need 25 gallons of gas to go 500 miles.
Answer:
x g(x)
1 −10
2 −12
3 −14
Step-by-step explanation:
Substitute the values and do the arithmetic.
Table values for x are 1, 2, 3. We only need to find g(1) to determine which table is the correct choice.
f(1) = 1 +4 = 5 . . . . . . . . . put 1 where x is and do the arithmetic
g(1) = -2·f(1) = -2·5 = -10 . . . . . matches the 3rd choice
