Answer: b)
Step-by-step explanation:
Given,
speed of train A travelling east = 55 mph
speed of train B travelling west = 70 mph
time train A travelled while train B was at rest = 45 min or ![(\frac{3}{4})hr](https://tex.z-dn.net/?f=%28%5Cfrac%7B3%7D%7B4%7D%29hr)
so, Distance travelled by train A while train B was at rest = ![55(\frac{3}{4} ) miles\\](https://tex.z-dn.net/?f=55%28%5Cfrac%7B3%7D%7B4%7D%20%29%20miles%5C%5C)
= ![41.25 miles](https://tex.z-dn.net/?f=41.25%20miles)
Now, after 'T' hour both the train will travel;
train A = 55T
train B = 70T
hence, the distance (D) between two train in miles will be;
⇒ D = 41.25 + 55T + 70T
⇒ D = 125T + 41.25
Answer:
70 standard boxes, 40 deluxe boxes
Step-by-step explanation:
standard: x
deluxe: y
x + y = 110
7x + 11y = 930
Multiply the first equation by 7 and subtract.
7x + 7y = 770
-(7x + 11y = 930)
You get -4y = -160
y = 40
Substitute y into the first equation.
x + 40 = 110
x = 70
Answer:
?
Step-by-step explanation:
Answer:
(B) A selected group of participants that is representative of a larger population
Step-by-step explanation:
A sample statistic is a piece of information that you get from a fraction of the population. This information is representative of a larger population.
For example, someone wants to conduct a survey about the most popular NFL team in Syracuse, NY, if it is the Buffalo Bills or the New York Giants. This person is not going to ask each person for whom they cheer. They are going to collect data from a fraction of the population and this data will be expanded to include the entire population.
So, the correct answer is:
(B) A selected group of participants that is representative of a larger population
Answer:
D. 5y^2 - 4y - 1
Step-by-step explanation:
Combine like terms:
(y^2 -y +1) +(4y^2 -3y -2)
= y^2(1 +4) +y(-1-3) +(1 -2)
= 5y^2 -4y -1