Intelligence Question sms

1 din mujy bazar jana pra.
mery pas paisy nai thy.
me ne 2 dostoon
(1 se 1000 or dosry se 500 rupy le liye.
Rasty me 1000 rupy gum ho gy.
500 se me ny 300 ka Saman ly liya mery pas 200 bach gy.
wapis aa k me ny dono ko 100,100 wapis kr diy.
abi jis ko 1000 dainy thy os k 900 reh gy
or jis ko 500 dainy thy os k 400 rehy gye.
jaisy
900+400=1300
Or 300 ka me Saman ly liya total mila k 1300+300=1600 ho gy magar mary pas 1500 tha 1600 kasy ho gy ???
Sir iska answer to btaen..m stuck!