Check sibling questions

Ex 3.5, 4 (i) - A part of monthly hostel charges is fixed and the rema

Ex 3.5, 4 (i) - Chapter 3 Class 10 Pair of Linear Equations in Two Variables - Part 2
Ex 3.5, 4 (i) - Chapter 3 Class 10 Pair of Linear Equations in Two Variables - Part 3
Ex 3.5, 4 (i) - Chapter 3 Class 10 Pair of Linear Equations in Two Variables - Part 4

This video is only available for Teachoo black users

Solve all your doubts with Teachoo Black (new monthly pack available now!)


Transcript

Ex 3.5, 4 Form the pair of linear equations in the following problems and find their solutions (if they exist) by any algebraic method : (i) A part of monthly hostel charges is fixed and the remaining depends on the number of days one has taken food in the mess. When a student A takes food for 20 days she has to pay Rs 1000 as hostel charges whereas a student B, who takes food for 26 days, pays Rs 1180 as hostel charges. Find the fixed charges and the cost of food per day. Let Fixed charge = Rs x & Charge per day taken food = Rs y per day Given that charge paid by student A for 20 days is Rs 1000 Fixed charge + 20 × (Charge per day) = 1000 x + 20y = 1000 Also, Charge paid by student B for 26 days is Rs 1180 Fixed charge + 26 × (Charge per day) = Rs 1180 x + 26y = 1180 Hence, our equations are x + 20y = 1000 …(1) x + 26y = 1180 …(2) From (1) x + 20y = 10000 x = 1000 – 20y Putting value of x in (2) x + 26y = 1180 (1000 – 20y) + 26y = 1180 – 20y + 26y = 1180 – 1000 6y = 180 y = 180/6 y = 30 Putting y = 30 in equation (1) x + 20y = 1000 x + 20(30) = 1000 x + 600 = 1000 x = 1000 – 600 x = 400 Hence, x = 400, y = 30 is the solution of the equations So, Fixed charges = x = Rs 400 Charge per km = y = Rs 30 per day

Davneet Singh's photo - Co-founder, Teachoo

Made by

Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.