Question

16. The cost of 3 Pens and 5 Pencils is Rs. 100. Also the cost of one Pen and one Pencil is in
the ratio of 5:1 respectively. What is the cost of one dozen Pens?
a) Rs.200 b) Rs.250 ) Rs.300 d) Rs. 150 e) None of these​

Answer 1

Answer:

C) Rs.300

Step-by-step explanation:

Pen: pencil =5:1

cost of per pencil = rs.5

cost of per pen = rs.25

3pens = 25*3=rs.75

5 pencils=5*5=rs.25. So,the total cost is 100(75+25)

cost of one dozen pens =12*25= rs.300

Answer 2

The cost of one dozen Pen is Rs.300. and option (c) is correct.

Step-by-step explanation:

Given:

3 Pens and 5 Pencils cost is Rs. 100.

One Pen and one Pencil cost is in the ratio of 5:1 respectively.

To Find:

The cost of one dozen.

Solution:

Let  the cost of one Pen is  q  and cost of one  Pencil is r .

As given- one Pen and one Pencil cost is in the ratio of 5:1 respectively.

$\frac{q}{r} =\frac{5}{1}$    

$r=\frac{q}{5}$   --------------- equation no.01.

s given - 3 Pens and 5 Pencils cost is Rs. 100.

$3q+5r=100$    ------------ equation no.02.

Putting value of r from equation no.01 to equation no.02.We get.

$3q+5\times \frac{q}{5} =100$

$3q+q=100$

$4q=100$

$q= Rs.\ 25$

The cost of one Pen is  Rs.25.

The cost of one dozen( 12 pens) $=12\times 25= Rs.300$

Thus, the cost of one dozen Pen is Rs.300 and option (c) is correct.

PROJECT CODE#SPJ3