Question

What is the cost of a packet of bread if 6 packets of bread and 3 packets of butter together cost Rs. 90 and a packet of butter costs thrice that of a packet of bread?

Answer 1

Hint: We will assume that the cost of 1 packet bread is Rs. x, then we will get the cost of butter as 3x and the cost of 6 packets of bread as 6x. Now, the cost of 6 packets of bread and three packets of butter can be represented in the equation as 6x + 3(3x) = 90. We will solve this linear equation and get the cost of one packet of read.

Complete step-by-step answer:
It is given in the question that we have to find the cost of a packet of bread if 6 packets of bread and 3 packets of butter together cost Rs. 90 and a packet of butter costs thrice that of a packet of bread.
So, let us assume the cost of one packet of bread as Rs. x. Then according to the question, the cost of 1 packet of butter will be 3x. Now, it is also given in the question that 6 packets of bread and 3 packets of butter together cost Rs. 90. So, we can write,
6x + 3(x) = 90
6x + 9x = 90
15x = 90
On dividing both the sides with 15, we will get,
$\dfrac{15x}{15}=\dfrac{90}{15}$
x = 6
Therefore, the cost of 1 packet of bread will be Rs. 6.

Note: It is observed that most of the students skip the line that the cost of bread is thrice the cost of butter as a result they may form the equation as 6x + 3x = 90, and on solving it further, they will get the answer as Rs. 10, which is wrong. Thus, it is recommended that the students read and understand the question properly.