Sum of all the 3 digit number formed by using digits 3, 4, 6 & 8 will be no digit is repeated in any

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17 Mar 2016 Three digit number

Sum of all the 3 digit number formed by using digits 3, 4, 6 & 8 will be no digit is repeated in any number.

OPtion

1) 14112
2) 15246
3) 13860
4) 12466
5) 13986
6) 13796
7) 12726
8) 14238
9) 12978
10)13482

Solution

Total combination are
3,4,6 and 3,4,8 and 3,6,8 and 4,6,8
in every pair 6 number are possible so total sum in very place
= 2[(3+4+6)+(3+4+8)+(3+6+8)+(4+6+8)]
= 2(13+15+17+18)
2(63) = 126
Net sum
12600+1260+126
13986
Option 5)

Correct Option: 5 Best Solution (3)

Rishu   8 years AGO

total number of combinations possible=4*3*2=24
total number of digits=4

so each digit will come 24/4=6 times at ones, tens and hundreds places of the total numbers formed by the combination of the 4 digits

sum of digits at ones place=6*(3+4+6+8)=126
so 6 comes at ones place & 12 is carry to tens place
sum of digits at tens place=6*(3+4+6+8)+12(carry)=138
so 8 comes at tens place & 13 is carry to hundreds place
sum of digits at hundreds place=6*(3+4+6+8)+13=139
so 9 comes at hundreds place & 3 and 1 occupies thousands & ten thousands place respectively

thus, the required sum is 13986

Like? Yes (6) | No   

Akshat Sood   8 years AGO

Get as much numbers from numbers like 3,4,6
4,6,8
6,8,3
4,8,3
take the sum we get 13986

Like? Yes | No (1)  

nagarajupalli chenchukiran   8 years AGO

4!/1!=24 and write 24 numbers and add them

Like? Yes | No (2)