Please help me to do these questions from number system thanks:
Amitesh buys a pen,pencil and an eraser for RS 41. if the least price is of pen that is 12 and eraser cost more than the pencil and pen costthe least.
Answer the following questions:
If it is known that the eraser cost is not dividible by 4 then the cost of the pencil is :
a)12 b)13 c)14 d)15 The answer is a)
Is the question correct? You mentioned that the least price of a pen is Rs. 12, and the pen is the cheapest among the three. So how can the answer be a pencil costing Rs. 12?? A pencil should atleast cost Rs. 13.
If we go exactly by your question, my answer to this question would be a pencil would cost Rs. 14.
We have Pen = 12
So, if Pen = 12, Pencil + E = 29, which could either be 13+16 or 14+15. No other pair would satisfy all the conditions
If Pen = 13, Pencil + E = 28, which could be 13+15 or 14+14. Both don't satisfy, as we can't have two objects at the same price.
Thus, Pen has to be at Rs. 12. Since the cost of an eraser is not divisible by 4, the pair of Pencil, Eraser would be 14,15.
A man sold 38 pieces of clothing.Ih he sold at least 11 pieces each item and he sold more shirts than trousers and more trousers than ties then the number of ties that he sold :
a) Exactly 11 b) Atleast 11 c)At least 12 d) Cannot be determined The answer is a) but i am getting b)
We'll have to proceed in exactly the same way.
Shirts > Trousers > Ties, S + Tr + Ties = 38
If Ties = 11, S + Tr = 27, which could be 12+15 or 13+14.
If Ties = 12, S + Tr = 26, which could be 12+14 or 13+13. Again, we can't have two objects at the same price.
Thus the answer is correct, exactly 11.
Find the least sqaure number divisible by 6,8 and 15
The answer is 3600
The least number should atleast be divisible by 6, 8 and 15. So we need to have atleast those prime factors which make up all of these numbers.
6 = 2*3
8 = 2*2*2
15 = 3*5
So the least number (just plain number, not square) which is divisible by 6, 8 and 15 is 2*3*2*2*5
This number contains 2*3, as well as 2*2*2, as well as 3*5
Now to make it a square, we just need to add one factor each of 2, 3 and 5, since there are only odd numbers of them.
Thus, the square would be: 2*3*2*2*5*2*3*5 = 3600
Find the least number by which 30492 must be multiplied or didvided so as to make a perfect square:
a)11 b)7 c)3 d) 2
the answer is b
Just find the factors of 30492 and find which of them is in odd multiples.
The factors are : 2*2*3*3*7*11*11
There's only one 7, so either multiply or divide by 7 to make the number a square.

