Question

15. Savita buys 12 masks and 3 sanitizer bottles for Rs. 590 to a hospital. Later she buys 3
more masks and 2 sanitizers for Rs.820. Identify the unknowns in the given situations
(Hint: Write the given situation in pair of linear equations in two variables.)​

Answer 1

Let cost of mask be x rs and cost of sanitizer be y rs

According to the first condition,

12x + 3y = 590 (1)

According to the second condition,

3x + 2y = 820 (2)

Multiplying equation (2) by 4

12x + 8y = 3280 (3)

Subtracting (1) from (3)

5y = 2690

$y = \frac{2690}{5} = 538$

Substituting y = 538 in (2)

3x + 2(538) = 820

3x + 1076 = 820

3x = 820 - 1076

3x = -256

$x = \frac{ - 256}{3}$