Question

Write the following sets in set-builder form :
a) A = {7,14,21,28,35,42,49}
b) B = {2,4,9,16,25,...}
c) C = {1,8,27,64,...}
d) D = {1,2,3,4,6,8,12,24}
e) E = {3,9,27,81,343}​

Answer 1

Step-by-step explanation:

C)

Let the cost price be x

Since profit is given as 20%, selling price will be (1+0.2)x

Thus, selling price would be 1.2x.

When C.P. and S.P. are Rs. 20 less then,

C.P. =x−20

S.P. =1.2x−20

According to the given condition,

Now, 1.2x−20=1.3×(x−20)

⇒1.2x−20=1.3x−26

⇒1.3x−1.2x=−20+26

⇒0.1x=6

⇒x=60

therefore, the cost price of the article is Rs. 60.