On the occasion of Diwali festival each student of a class sends greeting cards to the others. If there are 20 students in the class, then the total number of greeting cards exchanged by the students is

On the occasion of Diwali festival each student of a class sends greeting cards to the others. If there are 20 studentsin the class, then the total number of greeting cards exchanged by the students is

A
$^{20} C_{2}$
B
$^{2 \times 20} C_{2}$
C
$2 \times^{20} P_{2}$
D
none of these

Solution:

Required number $= 2 \times^{20} C_{2}$

Related content

SBTET Full Form

What is CSS Scholarship – Know About CSS (Central Sector Scholarship) Scholarship 2023

International Coffee Day

International Day for the Elderly

MPL Full Form – Mobile Premier League

How to Prepare for NTSE 2023-24: Best NTSE Preparation Tips?

RRB NTPC Eligibility 2023

NTSE (National Talent Search Exam) Scholarship Scheme: Details, Amount, Eligibility, Selection Process

Casual Leave Application for Office, Teachers, Government Offices with Format and Samples

NCVT Full Form – National Council for Vocational Training