An Integer is obtained by writing all positive integers from 1 to 60 i

Question

An Integer is obtained by writing all positive integers from 1 to 60 in following manner: 1234567891011121314 ……..585960. Find the 80th digit from left in this integer.

A. 9
B. 6
C. 5
D. 4
E. 2

Charli08 · Answer

80th number needed.

First subtract 9 to account for the first 9 numbers as they are all single digits:
80-9 = 71

All following numbers will be 2 digits.
Dividing by 71 by 2 since the numbers are 2 digits will give us the last 2 digits number with remainder 1:
71/2 = 44 + R1
==> 70th digit is 4

We know that the next number is 45, hence out 71st digit is 4
===>  D

brt · Answer

123456789- total 9
80th term is asked so....80-9=71
70=35*2 which implies there are 35 two digit numbers including 10
so, 10+35=45 
after 45 we have 46 but we want only 4 ( as only one more number is required to make the 80th term)
so ans is 4

sayan640 · Answer

from 1 - 9 = 9 digits
from 10 - 60 = 51 numbers == 102 digits
9 + 2*n = 80
n = 35.5
total 35 numbers from starting from 10 till we reach the 80th digit are here.
35th number = 10 + 34*1 = 44..Till 44 , we get 35*2 + 9 = 79 digits..The next number is 45.
The 80th digit is 4 from the number 45.

An Integer is obtained by writing all positive integers from 1 to 60 i

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An Integer is obtained by writing all positive integers from 1 to 60 i

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