A committee must be formed with 4 teachers and 5 students. If there are 7 teachers to choose from, and 15 students, how many different ways could the committee be made?

Step-by-step explanation:

There are a total of 10 persons (6 teachers + 4 students) from which a committee of 5 is to be formed. This can be done in 10C5 ways.

The number of ways that a committee can be formed with no students in it is to select 5 teachers out of the pool of 6 teachers available. This can be done in 6C5 ways.

Therefore the total number of ways that the committee can be formed with at least one student in it is 10C5 - 6C5.

10C5 = 252

6C5 = 6

Therefore the required number of ways = 246

the correct option is 2.

step-by-step explanation:

according to the given information triangle abc is a right angle triangle with right angle at a. segment ab is 5 and segment ac is 7. point d is on segment bc and angles adb and adc are right angles.

it is given that triangles abd, cad, and cba are similar.

two triangles are similar if their corresponding sides are proportional.

in triangle cba, using pythagoras theorem

                      )

triangle abd and cba are similar,

                            (2)

triangle cad and cba are similar,

                      )

using (1), (2) and (3), we get

hence proved.

therefore option 2 is correct.