Answer:
The info that tells that you have to add is how many hours he practiced in total on the first two days. The info that tells you to subtract is how many more hours did he practice on Tuesday.
Step-by-step explanation:
well, we know that 1ft³ = 7.48 gallons, alright, we have a volume in gallons and a diameter in feet, so if we were to use the diameter in feet to get the volume what we would end up will be a volume in ft³, so let's convert firstly the gallons to ft³ then
why do I use a fraction? for the sake of not losing value in the rounding, so let's use the fraction for the volume of a right-circular cylinder
Answer:
21
Step-by-step explanation:
In order to form a chord you need to:
- Select one point. You have 7 choices
- Select a another point. You have just 6 choices because you have to dicard the point alredy chosen
- Connect the two points with a chorde
Since we have 7 choices for the first point and 6 for the second one, one might think that there are a total of 7*6 = 42 choices.
However the correct answer is 21, because you have to take into the account that selecting the point A first and selecting the point B on second step is the same than selecting the point B first and then the point A, because the chord is the same.
Therefore we are counting each chord twice, and we have to divide the result by 2, obtaining 7*6 / 2 = 21.
You can also calculate the amount by using the combiatorial number. The total amount of possibilities to select k elements from a set of n, with n higher than or equal to k and both positive, without taking into account the order is the combinatorial number of n with k, given by
In this case, in order to form a chord we need to select 2 points of the seven we are given, ignoring order, thus the total amount of possibilities is
As we calculated before.
-5 is essentially -1·5
Order of operations says to do exponents first, so without parentheses -5², you would square first then multiply by -1, leaving you with an answer of -25.
However, parentheses comes before exponents in order of operations, so with parenthesis (-5)² would be 25.
Step-by-step explanation:
we simply need to get the total distance and the total time and put them into relation, norming it to distance in 1 hour. after all, speed is always an average number over a period of time (even if it is a tiny period of time).
the total distance is
72 + 69 = 141 km
he drove 69 km going 60 km/h.
how much time did he need ?
we need to get the hours out of an expression of km and h.
so, we need to do
69 km × 1/60 km/h = 69 h / 60 = 69 minutes = 1.15 hours =
= 1 h 9 minutes
so, the total time was
48 + 69 = 117 minutes = 117/60 = 1.95 hours
the average speed for the whole trip was then
141 km / 1.95 h = 141/1.95 km / 1 h = 72.30769231... km/h