true

Take Class 12 Tuition from the Best Tutors

Affordable fees
1-1 or Group class
Flexible Timings
Verified Tutors

Search in

Algebra (JEE - Main )

Sujoy Das

10/02/2018 0 0

Question:

A sequence of numbers is written in the following fashion: 1, 7, 1, 1, 7, 7, 1, 1, 1, 7, 7, 7, ... till ‘n’ terms. The sum of first 5001 terms of the given sequence is,

a) 5001 b) 20478 c) 19911 d) 39822

Answer:

n(n+1) = 5000, n = 70,

total = 1/2(70*71 + 7*70*71) + 31.

70 terms of 7 and of 1 plus 31 more terms

35*71*(7+1) =19880 + 31

= 19911

Sum has to be odd so A or C

But obviously sum > 5001

Hence C.

0 Like 0 Dislike

Follow 2

Other Lessons for You

Did you know?

PERIODIC TABLE- Periodic Laws- Genesis of Periodic Classification After the proposal of John Dalton's Atomic Theory, the scientists took Atomic Weight as the important property of element and tried...

Neeta T.

0 0

Effective study habits

Effective study Habits, we are creature of our habits. Substitute bad habits of learning with good habits of learning. Right attitude. Approach the material you are studying with right attitude. Get...

Sunil Sikri

2 0

Synfig Tutorial for Std 11 Science and Commerce

Lesson:1 Std-11th Introduction to Multimedia: Communication is an integral part of our life. We use various means of communication like radio, newspaper, television, theatre, movies, internet and others....

Jinal

0 0

How To Find Antilogs Value By Calculator

To find antilog value i.e. AL(m):- First type m.(where m= any number like 1, 2, 3 etc.) Then type ÷ button Then type 227695 Then type + button Then type 1 Then type = button Type continious...

Rohit Singh

0 0

Introduction To Accounting: Part 1: Need For Accounting

Whenever we start doing business, a number of transactions take place. For example, if we start a business of say, a book store (i.e. we’ll be buying books from wholesalers and publishers, and selling...

Nishant Kumar

0 0

Find Class XII Tuition near you

Online Tuition Class 12

Looking for Class 12 Tuition ?

Learn from Best Tutors on UrbanPro.

Are you a Tutor or Training Institute?

Join UrbanPro Today to find students near you

Class 12 Tuition Questions

Which is the best book to teach PUC 1st year accountancy (Board State)?

15 Answers

Magnetic effects of current 1 what is lenz law? 2 explain briefly MCG?

11 Answers

Why density of Ice is lesser than water?

62 Answers

The sum of ages of 5 children born at the intervals of 3 years each is 50 years. What is the age of the...

9 Answers

This is a question for students of commerce stream. Human resource is not shown as an asset in the...

11 Answers

Looking for Class 12 Tuition Classes?

The best tutors for Class 12 Tuition Classes are on UrbanPro

Select the best Tutor
Book & Attend a Free Demo
Pay and start Learning

Take Class 12 Tuition with the Best Tutors

The best Tutors for Class 12 Tuition Classes are on UrbanPro

I am a Student I am a Tutor
Name*	Please enter your full name. Please enter institute name.
Email*	Please enter your email address.
Phone*	Please enter a valid phone number.
Location*	Please enter a pincode or area name.
City*	Please enter city name.
Category*	Please enter category.
Gender*	Male Female Please select your gender.
Email ID/ Mobile No.*	Please enter either mobile no. or email.
Enter Password*	Please enter OTP Please enter Password Sorry, this phone number is not verified, Please login with your email Id.