$7$ chairs and $4$ tables for a classroom cost Rs. $7000$ , while $5$ chairs and $3$ tables cost Rs. $5080$ . Find the cost of each chair.

Open in App

Solution

$L e t c o s t o f c h a i r = x R s a n d c o s t o f t a b l e = y R s$

$t h e n 7 x + 4 y = 7000 \to (1)$

$a n d 5 x + 3 y = 5080 \to (2) m u l t i p l y e q u a t i o n (1) b y 3 a n d e q u a t i o n (2) b y 4, w e g e t$

$21 x + 12 y = 21000 \to (3) a n d 20 x + 12 y = 20320 \to (4)$

$s u b t r a c t e q u a t i o n (3) a n d e q u a t i o n (4), w e g e t$

$x = 680 R s$

$∴ 7 x + 4 y = 7000 o r 4 y = 7000 - 7 x ∴ y = (\frac{7000 - 7 x}{4})$

$= (\frac{7000 - 7 (680)}{4}) = 560 R s$

Suggest Corrections

Similar questions

5 chairs and 4 tables together cost Rs.5600,while 4 chairs and 3 tables together cost Rs.4340.Find the cost of a chair and that of a table.

3

2

R s . 700

5

3

R s . 1100

2

2

4

3

2100

5

2

1750

Join BYJU'S Learning Program