Question

are
If 20 points. marked on a cinde, how
many chonds can be drawn?​

Answer 1

the process in which movement of pollen grains is known as pollination

Answer:

Step-by-step explanation:

Answer 2

Question :

If 20 points are marked on a circle , then how many chords can be drawn.

Concept :

Chord : The line joining any two points on the circle is called chord.

Solution :

We have given 20 points out of which we have to select two points to draw a chord.

We can do this in $\tt {}^{20}{C}_{2}$ ways.

$\tt {}^{20}{C}_{2} = \frac{20!}{(20-2)!2!}$

$\tt \implies {}^{20}{C}_{2} = \frac{20!}{18!2!}$

$\tt \implies {}^{20}{C}_{2} = \frac{20×19×18!}{18!2!}$

$\tt \implies {}^{20}{C}_{2} = \frac{20×19}{2}$

$\tt \implies {}^{20}{C}_{2} = \frac{380}{2}$

$\tt \implies {}^{20}{C}_{2} = 190$

190 chords can be drawn.

Note :

I m also a maharashtrian.