In an examination of 500 marks (5 subjects & 100 marks for each subject), Amit got first class certi

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21 May 2014 Solve

In an examination of 500 marks (5 subjects & 100 marks for each subject), Amit got first class certificate with 67.8 %. If he got perfect square marks in all the subjects, then what are the number of possible methods for taking these marks in all the subjects.

OPtion

1) 28
2) 20
3) 4
4) 120
5) 15
6) 12
7) 60
8) 30
9) 243
10) None of these

Solution

The possible combination of marks is 49, 64, 64, 81, 81 Total number of methods for providing 81 marks for any 2 subjects out of 5 subjects is 10, then number of methods for providing 64 marks for any 2 subjects out of remaining 3 subjects is 3, then 49 marks is provided for the last subject. Hence total number of methods are 10*3*1 = 30

Option 8)

Correct Option: 8 Best Solution (5)

Prerna   10 years AGO

Amit got first class certificate with 67.8 %.
i.e. 339 out 0f 500.
If he got perfect square marks in all the subjects,
then he got 81 in 2 subjects, 64 in 2 subjects and 49 in one subject.
number of possible methods for taking these marks in all the subjects = 5!/(2!*2!)= 120/4=30

Like? Yes (7) | No (1)  

Ramsb   10 years AGO

67.8%=339 marks
amit got 64,64,49,81,81
then 5!/2!.2!
120/4=30

Like? Yes (3) | No (1)  

Ann Theressa   10 years AGO

Percentage marks = 67.8
total marks = 67.8*5 = 339

Since he got perfect square marks in all subjects
His marks can be
49,64,81 and 100

49+64+64+81+81 = 339

No of possible ways for taking these marks = 5!/(2!*2!) = 30

Like? Yes (3) | No (3)  

DILEEP KUMAR   10 years AGO

marks are 64,64,81,81,49
possibilities 5!/2!*2! = 30

Like? Yes (3) | No (3)  

Varunraj Reddy   10 years AGO

The possible ways are (64,64,49,81,81)

These values can be arranged in 5!/(2!*2!) ways

Total no.of possible methods=120/4=30

Like? Yes (2) | No (2)