Question

13 have Rs 1000 in ten and five rupee notes. If the number of ten rupee notes that I ha
is ton more than the number of five rupee notes, how many notes do I have in en
denomination
18 At a party, colas, squash and fruit juice were offered to guests. A fourth of the gue
drank colas, a third drank squash, two fifths drank fruit juice and just three did
drink any thing. How many guests were in all?
17. There are 180 multiple choice questions in a test. If a candidate gets 4 marks for ev
correct answer and for every unattempted or wrongly answered question one mar
deducted from the total score of correct answers. If a candidate scored 450 mark​

Answer 1

Answer:

13) Let no. of five rupee notes = x

     no. of ten rupee notes = x+10

Cost of 5 rupee notes = Rs. 5x

Cost of 10 rupee notes = Rs. 10x +100

Total Cost = Rs. 1000

Therefore,

5x + 10x + 100 = 1000

15x = 1000 - 100

15x = 900

x = 900/15 = 60

Therefore, No. of five rupee  notes = 60

No. of ten rupee notes = 60 + 10 = 70

18) Let there were x no. of guests.

Then 1/4*x had Coles,

1/3*x had squash &

2/5*x had fruit juice .

3 guests didn't had any of them.

Then total no. of guests ,those who had any of them is =1/4*x+1/3*x+2/5*x

=x(1/4+1/3+2/5)

=x(15+20+24)/60

=x*59/60

Then rest of guests are=x-x*59/60

=x/60

But we know 3 guests didn't had anything.

So,

x/60=3

or x=3*60

=180 (ans)

17) Let x be the number of questions attempted correctly.

Since for every correct answer 4 Mark's are awarded and for every wrong answer or unattempted question one mark is deducted.

Number of wrong answers or unattempted question =(180-x).

Total score=4x-(180-x)×1

=4x-180+x

Total score =450

450=4x-180+x

450=5x-180

5x=630

X=630÷5=126

Therefore, 126 answers he attempted correctly.

Thanks.

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