A four digit number is to be formed using the digits 1 to 7
All digits of the number are different and repetition is not
allowed.
1. How many such numbers can be formed ?
2. How many such numbers are divisible by 4 ?

Answers were Sorted based on User's Feedback



A four digit number is to be formed using the digits 1 to 7 All digits of the number are different ..

Answer / sumati

Answer 1:
At unit's place 7 possibilities r dere.
At ten's place 6,
At hundred's place 5,
At thousand's place 4.

Therefore, 7*6*5*4=840

Answer 2:
for any number to b divisible by 4, the last two digit must
b divisible by 4. Such 2 digit combinations possible are.....
12,16,24,32,36,52,56,64,72,76.
At last two places, any one combination out of these 10 is
possible. For first two digits in the 4 digit number, the
possible combinations are 5*4=20
So there r 20*10=200 numbers divisible by 4.

Is This Answer Correct ?    71 Yes 7 No

A four digit number is to be formed using the digits 1 to 7 All digits of the number are different ..

Answer / purvi

Ans-200

I see with 1..7 if last 2 digits are
12,16,24,32,36,52,56,64,72,76...then the no. is divisible by 4

means last 2 digits has possible 10 Combinations

So Answer=P(5,2)*10=20*10=200

its correct!!!!!!!!!!!!!

Is This Answer Correct ?    16 Yes 4 No

A four digit number is to be formed using the digits 1 to 7 All digits of the number are different ..

Answer / satyam4friends

the total numbers are formed are 7.6.5.4=840
the numbers that are divided by 4 are= 7.6.5.3=630

Is This Answer Correct ?    45 Yes 38 No

A four digit number is to be formed using the digits 1 to 7 All digits of the number are different ..

Answer / hh

I see with 1..7 if last 2 digits are
12,16,24,32,36,52,56,64,72,76...then the no. is divisible by 4

means last 2 digits has possible 10 Combinations

So Answer=P(5,2)*10=20*10=200

its correct!!!!!!!!!!!!!

Is This Answer Correct ?    6 Yes 0 No

A four digit number is to be formed using the digits 1 to 7 All digits of the number are different ..

Answer / iii

Answer 1:
At unit's place 7 possibilities r dere.
At ten's place 6,
At hundred's place 5,
At thousand's place 4.

Therefore, 7*6*5*4=840

Answer 2:
for any number to b divisible by 4, the last two digit must
b divisible by 4. Such 2 digit combinations possible are.....
12,16,24,32,36,52,56,64,72,76.
There are total 7 nos
out of which a 4 digit no is to be formed.
7 nos can be arranged in 7! and 4 digit no. can be formed
in 4*7! ways
At last two places, any one combination out of these 10 is
possible. For first two digits in the 4 digit number, the
possible combinations are 5*4=20
So there r 20*10=200 numbers divisible by 4.

Is This Answer Correct ?    2 Yes 0 No

A four digit number is to be formed using the digits 1 to 7 All digits of the number are different ..

Answer / deepanjeyakumar

Answer1 840;
Answer2 180;

Is This Answer Correct ?    3 Yes 14 No

A four digit number is to be formed using the digits 1 to 7 All digits of the number are different ..

Answer / ?

how am i supposed to know?

Is This Answer Correct ?    2 Yes 13 No

A four digit number is to be formed using the digits 1 to 7 All digits of the number are different ..

Answer / guest

5040
1260

Is This Answer Correct ?    13 Yes 29 No

A four digit number is to be formed using the digits 1 to 7 All digits of the number are different ..

Answer / r.ravi kiran

1)1 four digit number
2)1

Is This Answer Correct ?    5 Yes 22 No

A four digit number is to be formed using the digits 1 to 7 All digits of the number are different ..

Answer / guest

1.only one
2.none

Is This Answer Correct ?    2 Yes 19 No

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The other 20 students (the control group) went to bed by 11:00 p.m. on the evening of the test. The test scores for each group are shown in the graphs below. Each dot on the graph represents a particular student’s score. For example, the two dots above 80 in the bottom graph indicate that two students in the sleep group scored 80 on the test. . . . . . . . . . . . . . . . . . . . . 30 40 50 60 70 80 90 100 Test Scores: No- Sleep Group . . . . . . . . . . . . . . . . . . . . 30 40 50 60 70 80 90 100 Test Scores: Sleep Group Examine the two graphs carefully. Then choose from the 6 possible conclusions listed below the one you most agree with. a. The no-sleep group did better because none of these students scored below 40 and, a student in this group achieved the highest score. b. The no-sleep group did better because its average appears to be a little higher than the average of the sleep group. c. 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All three results are equally likely 40. When three dice are simultaneously thrown, which of these three results is LEAST LIKELY to be obtained? a. Result 1: A 5, a 3 and a 6 b. Result 2: A 5 three times c. Result 3: A 5 twice and a 3 d. All three results are equally unlikely

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