Question

A shopkeeper charges sales tax of x% up to Rs. 2,000 and
above it he charges y%A customer pays total tax of Rs 320,
when he purchases the goods worth Rs. 6,000 and he pay's
the total tax of Rs. 680 for the goods worth Rs. 12,000. The
value of (x - y) is :
(a) 0
(b) - 2
(0) - 4
(d) 5​

Answer 1

(i)

x% of 2000 = x/100 × 2000

                  = 20x

(ii)

y/100 × (6000 - 2000) = y/100 × 4000

                                     = 40y

Now :

20x + 40y = 320..................1)

Case 2

x% of 2000 = 20x

y% of (12000 - 2000) = y/100 × 10000 = 100y

20x + 100y = 680...........................

Solving 1 and 2 simultaneously to get y and x:

20x + 40y = 320

20x + 100y = 680

Subtract 1 from 2 we have :

60y = 360

y = 360/60

y = 6%

Substitute this in 1 we have :

20x + 40(6) = 320

20x = 320 - 240

20x = 80

x = 80/20

x = 4%

Now :

(x - y) = (4% - 6% ) = -2%