Thank you for registering.

One of our academic counsellors will contact you within 1 working day.

Please check your email for login details.
MY CART (5)

Use Coupon: CART20 and get 20% off on all online Study Material

ITEM
DETAILS
MRP
DISCOUNT
FINAL PRICE
Total Price: Rs.

There are no items in this cart.
Continue Shopping

A password, which consists of the digits from 0 to 9, and is of length 4 that uses exactly 2 different digits. How many different passwords can there be?

A password, which consists of the digits from 0 to 9, and is of length 4 that uses exactly 2 different digits. How many different passwords can there be?

Grade:11

1 Answers

India VK
42 Points
7 years ago

Choose 2 digits out of 9 in 9C2 ways. Next permute these 2 digits into 4 places - which can be done in 4!/2!2! ways

 

So total number of ways = 9C2. 4!/2!2!

Think You Can Provide A Better Answer ?

Provide a better Answer & Earn Cool Goodies See our forum point policy

ASK QUESTION

Get your questions answered by the expert for free