A dishonest dealer professes to sell goods at the cost price but uses a false weight and gains 25%. Find his false weight age?

A. 700 gms
B. 750 gms
C. 800 gms
D. 850 gms
Explanation:
25 = E/(1000 – E) * 100
1000 – E = 4E
1000 = 5E => E = 200
1000 – 200 = 800