Answer:
Rs 800
Step-by-step explanation:
Selling Price =Rs640
Loss=20%
Let the cost price of the watch be Rs x.
SP=CP-20%of CP
or, 640=x-x/5
or, 640=4x/5
or, 4x=640*5
or,x=3200/4
Therefore, x=Rs 800. The cost price of the watch is Rs 800.
s
0, -1 for part A -1,-9 for part B
There are two critical points, at which we have
x=y-48, y=x+48