I can't really help you with the math but I can give you the formulas for the answers.
Answer:
(a) t = 1.6766
Step-by-step explanation:
n = 50
degree of freedom = n - 1 = 50 - 1 = 49
confidence level = 90%
The critical value corresponding to 90% confidence level and 49 degrees of freedom is obtained by interpolating between 48 and 50 degrees of freedom (df)
Let the critical value at 49 df be y
dof. critical value
48. 1.677
49. y
50. 1.676
(49 - 48)/(50 - 48) = (y - 1.677)/(1.676 - 1.677)
0.5 × -1×10^-3 = y - 1.677
y - 1.677 = -5×10^-4
y = -5×10^-4 + 1.677 = 1.6765
The closest option is (a)
Answer:
40°
Step-by-step explanation:
Because triangle QSR is isosceles ∠SQR=∠SRQ=35°. The sum of the angles in a triangle is 180°, so ∠QSR=180°-35°-35°=110°. The measure of a straight line is 180°, so ∠PSQ=180°-110°=70°. Because triangle PSQ is also isosceles ∠PSQ=∠PQS=70°. Then, ∠QPS=180°-70°-70°=40°.
Answer:
6 pounds of coffee.
Step-by-step explanation:
First, we determine how much money she spent. 80-31.76 = 48.24
Next, we divide the money spent by the price per unit. 48.24/8.04=6
Therefore, she bought 6 pounds of coffee.