Question

-If the cost of 37 pens and 53 pencils together is 320, while 53 pens
and 37 pencils together cost 400. The cost of two pens is:
(1) * 5.50
(2) १ 1.50
(3) * 13.00
(4) { 15.00
यदि 37 कलम व 53 पेन्सिल की कुल कीमत 320 में हैं जबकि 53 काम व
37 पेन्सिल की कीमत 400 * है, तो दो कलम की कीमत होगी :
(1) 6.50 है।
(2) 1,50 रै।
(3) 13.00 १
(4) 15.00 १
​

Answer 1

Answer:

The cost of two pens is Rs. 13

option (3) is correct

Step-by-step explanation:

Let x and y be the cost of one pen and one pencil respectively.

As per given data,

37x+53y = 320...........(1)

53x+37y = 400...........(2)

Adding (1) and (2)

90x + 90y = 720

simplify we get

x + y = 8..............(3)

(1) - (2) we get

-16x + 16y = -80

simplify we get

- x + y = -5...........(4)

(3) - (4) we get

2x= 13

The cost of two pens is Rs. 13

Answer 2

Answer:

Cost of Two Pen = Rs 13

option 3 is correct

Step-by-step explanation:

-If the cost of 37 pens and 53 pencils together is 320, while 53 pens

and 37 pencils together cost 400

Let say pen cost = Rs M

Let say Pencil Cost = Rs N

37M + 53N = 320   - eq 1

53M + 37N = 400   - eq 2

Adding both eq 1  + eq 2

90M + 90N = 720

dividing by 90

=> M + N = 8   - eq 3

Eq 2 - Eq1

16M - 16N = 80

Dividing by 16

M - N = 5    - eq 4

Eq3 + eq 4

2M = 13

Cost of Two Pen = Rs 13

option 3 is correct