Latest Elitmus Aptitude Question SOLUTION: how many 4 digit no can be made from 2,3,4,5,6,7 that divide by 25.

• Placement Papers
• /
• Elitmus
• /
• Numerical Ability
• /
• Permutation and Combination

Elitmus Question Papers:

(#M40033524) ELITMUS Numerical Ability question permutation Keep an EYE

how many 4 digit no can be made from 2,3,4,5,6,7 that divide by 25.

Asked In Elitmus Ayush Rastogi (10 years ago)

Unsolved Read Solution (9)

Is this Puzzle helpful?   (4)   (0) Submit Your Solution Permutation and Combination

Read Solution (9) :

sanjana  (10 years ago)

In order for a number to be divisible by 25, the number must end in 00, 25, 50, or 75.
No zero is in the list of options, so 00 or 50 cannot be possible.
25 and 75 are possible. So working backwards:

ones digit: must be a 5. Only 1 option.
tens digit: can be a 2 or 7. 2 options.
100s digit: can be any of the remaining 4 numbers left.
1000s digit: can be any of the remaining 3 numbers left.

So multiply each digit's "options" to get the answer:

1 * 2 * 4 * 3 = 24

Is this solution Helpfull? Yes (18) | No (5)  

sanjana  (10 years ago)

If repetition is allowed then d ans will be diff..
ones and tens digits are still the same at 1 and 2 respectively, since it still has to be divisible by 25.

But the other two digits can then be any of the 6 numbers.

So that gives us:

1 * 2 * 6 * 6 = 72

Is this solution Helpfull? Yes (13) | No (3)  

Hariom Sharma  (10 years ago)

at unit place only 5
nd 2nd place only 2,7
so total no. are
4*3*2*1=24

Is this solution Helpfull? Yes (2) | No (3)  

vibhor  (10 years ago)

how it can be 24 ....

calculate it by this way

For number which start with 2

2225,2275

2325,2375,

2425,2475

2525,2575

2625,2675

2725,2775

similarly for number which start with 3,4,5,6,7

so total number we got is 12*6=72

Is this solution Helpfull? Yes (2) | No   

chanchal singh  (10 years ago)

numer will be divisible by 25 if we have 25 and 75 as last 2 digit
in this case

total number will be
if last 2 digit are 25 then= 6*6 way for first 2 digit
and if last 2 digit are 75 then=6*6 for first 2 digit

so total 36+36=72 number can be formed

Is this solution Helpfull? Yes (1) | No (1)  

sakti prasad mohanty  (10 years ago)

since we need to fill 4 places the unit place filled by 5 that is 1way.then the rest in 5,4,3 ways.so ans is 60.

Is this solution Helpfull? Yes | No (4)  

Sandeep Kumar  (10 years ago)

to divide number by 25.......last 2 numbers must be 25 or 75
so they are fixed....
therefore,

No. of digits divisible by 25 are = 1*2*3*4 = 24

Is this solution Helpfull? Yes | No (1)  

deep chandra bhatt  (10 years ago)

ques ye tha how many four digit can be formed using 2,3,4,5,6,7 only once divisible by 25
a 12
b 20
c 24
d 40

Is this solution Helpfull? Yes | No   

akshay  (10 years ago)

4 digit no means
_ _ _ _ = ?

Solution- if the repetition is allowed then
_ _ 25 =?
we know that Total numbers are (i.e) 2, 3 , 4 , 5, 6 , 7 = 6
now we have to fill 2 digits of _ _ 24
So in this 1st disit 6 numbers can come and in the second digit also 6 numbers can come so 6 * 6 = 36
so in this way _ _ 24 = 36 numbers

like this way only

_ _ 75 = 6 * 6 = 36 numbers

so total 36+36 =72

But if the digits are not repeted then _ _ 25 = 1st digit can be of 4 numbers and 3 numbers so 4 * 3 =12

so total 12+ 12 = 24
:)
like this only _ _ 75 = 1st digit can be of 4 numbers

Is this solution Helpfull? Yes | No   

Please Login to Read Solution.