Question

If 5 pencils and 3 pens together cost of rs 35 whereas 2 pencils and 4 pens together cost rs 28 find cost of one pencil and one pen

Answer 1

Answer:

So for this qn u can either used the elimination method or the simultaneous

the equation will be like this

Take x= number of pencils

Take y= number of pens

 5x+3y=35

 2x+4y=28

(U have to multiply it by a number which will give u the same number on both sides, in this case we can use 4 and 3, 4 on the top and 3 for the bottom)

20x+12y=140

6x+12y=84

12 and 12 cancels out since they both are the same number

then u subtract the top number by the bottom number you get

14x/14=56/14

x=4

5(4)+3y=35

20+3y=35

3y=35-20

3y/3y=15/3y

y=5

To check if your correct or not plug in the values you got to the equation

First equation:

5(4)+3(5)

20+15=35

Second equation:

2(4)+4(5)

8+20=28

Final answer

cost of 1 pencil= 4

cost of 1 pen= 5

Plz mark it as brainliest

Answer 2

Answer:

• Cost of One Pencil(a) =3
• Cost  of One Pen(b) =5

Explanation:

Given :

• 5 pencils and 3 pens together cost of ₹ 35
• 2 pencils and 4 pens together cost ₹ 28

To Find :

Cost of one pencil and one pen

Solution :

Let pencil be “a” and let pen be “b”

5a+7b=50.........(1)

7a+5b=46..........(2)

multiply (1) by 7

35a+49b = 350

multiply (2) equation by 5

35a+25b=230

Solving them we get

24a=120

=> a = 5 rupees

By Substituting in second equation we get

b = 3 rupees