Question

In a colony, there are 55 members. Every
member posts a greeting card to all the
members. How many greeting cards
were posted by them?
1.990
. 2 890
3.2970
4. 1980​

Answer 1

the answer to your question is 2970

because every one perosn can give greeting cards to other 54 person.

so that means 54( 55 times) × 54 × 55 = 2970.

2970 greeting cards were posted by them all.

Answer 2

2970 greeting cards were posted by 55 members

Given :

• In a colony, there are 55 members.

• Every member posts a greeting card to all the members.

To find :

Number of greeting cards were posted by 55 members

1. 990

2. 890

3. 2970

4. 1980

Solution :

Step 1 of 2 :

Write down total number of members

Here it is given that there are 55 members in the colony

Step 2 of 2 :

Calculate number of greeting cards were posted by 55 members

First we calculate number of choices for each member.

1st member can post greeting card to (55 - 1) = 54 members [ As the person can not post greeting card to himself]

Number of choices for 1st member = 54

2nd member can post greeting card to (55 - 1) = 54 members [ As the person can not post greeting card to himself]

Number of choices for 2nd member = 54

Since every member posts a greeting card to all the members.

So this will continue for each of the 55 members

∴ Number of greeting cards were posted by 55 members

= 55 × 54

= 2970

Hence the correct option is 3. 2970

━━━━━━━━━━━━━━━━

Learn more from Brainly :-

$1.$ If 7. 5pr = 7pr – 1, then find r.(question based on permutation and combination chapter)

https://brainly.in/question/26877723

2. If nPr = 3024 and nCr = 126 then find n and r.

https://brainly.in/question/29044585

#SPJ3