Question

The cost of 4pen and 4pencil cost rs.100. 3times the cost of a pen is RS.15 more than cost of pencil box. Form a linear equation for above situation and find the cost of pen and pencil

Answer 1

Answer:

pen = ₹10

pencil = ₹15

Step-by-step explanation:

let the cost of pen be x

& pencil be y

now

4x + 4y = 100

=> 4(x + y) = 100

=> x + y = 25...... (i)

&

3x = y + 15......(ii)

from eq (i) we get

x + y = 25

or

y = 25 - x

putting this value of y in eq (ii) we get

3x = y + 15

=> 3x = (25 - x) + 15

=> 3x = 25 + 15 - x

=> 3x = 40 - x

=> 3x + x = 40

=> 4x = 40

=> x = 40/4

=> x = 10

now

putting this value of x in eq (i) we get

x + y = 25

=> 10 + y = 25

=> y = 25 - 10 = 15

so

cost of each pen = ₹10

cost of each pencil = ₹15

Answer 2

Hi!

Your answer is here,