(A) For x representing the cost of one of Tanya's items, her total purchase cost 5x. The cost of one of Tony's items is then (x-1.75) and the total of Tony's purchase is 6(x-1.75). The problem statement tells us these are equal values. Your equation is ...
... 5x = 6(x -1.75)
(B) Subtract 5x, simplify and add the opposite of the constant.
... 5x -5x = 6x -6·1.75 -5x
... 0 = x -10.50
... 10.50 = x
(C) 5x = 5·10.50 = 52.50
... 6(x -1.75) = 6·8.75 = 52.50 . . . . . the two purchases are the same value
(D) The individual cost of Tanya's iterms was $10.50. The individual cost of Tony's items was $8.75.
Answer:
A certain company makes 12-volt car batteries. After many years of product testing, the company knows that the average life of a battery is normally distributed, with a mean of 50 months and a standard deviation of 9 months. If the company does not want to make refunds for more than 10% of its batteries under the full-refund guarantee policy, for how long should the company guarantee the batteries?
The company should guarantee the batteries for 38 months.
Step-by-step explanation:
Using standard normal table,
P(Z < z) = 10%
=(Z < z) = 0.10
= P(Z <- 1.28 ) = 0.10
z = -1.28
Using z-score formula
x = zσ + μ
x = -1.28 *9+50
x = 38
Therefore, the company should guarantee the batteries for 38 months.
Answer:
B
Step-by-step explanation:
Line B best fits the data because some of the points fall on line B.
Hope this helps!
Answer:
0.15
Step-by-step explanation:
9.70-8.95= 0.75
0.75÷5= 0.15
