The average (arithmetic mean) length per film for a group of 21 films is t minutes. if a film that runs for 66 minutes is removed from the group and replaced by one that runs for 52 minutes, what is the average length per film, in minutes, for the new group of films, in terms of t ?

Step-by-step explanation:

The average (arithmetic mean) length per film for a group of 21 films is t minutes

A film that runs for 66 minutes is removed from the group and replaced by one that runs for 52 minutes

So,

Hence the average length per film, in minutes, for the new group of films, in terms of t is

900 degrees

step-by-step explanation:

d) by the cross product property, ab^2 = bc multiplied by ad

step-by-step explanation:

we are given

in the given triangle abc

angle a is 90° and segment ad is perpendicular to segment bc

we can see that

triangle(abc) and triangle(abd) are similar because they have common side and same angle (90 degree)

so, triangles(abc) and abd are similar

since, they are similar

so, the ratio of their sides must be equal

we get

now, we can cross multiply

and we get

so, this could be step to prove it