funny maths

just came back from PTSL
went there since 10am ...
a really funny Maths joke i got it today....

I went for waffle in Pusanika there with my friend.
a waffle cost RM2.20 and we ordered 2
and my friend also bought a cup of sweet corn which cost him RM2.20
he paid with RM10 and the Malays girl ask for syiling
and he ask for my help...
the malay girl took RM0.70 from me but she return RM6.80 to my friend...
?????
sweat...then why she want to get RM0.70 from me???
and her maths got serious problem as she should return RM6.30 to my friend only ma....

another case....when i got my waffle...
they thought that my friend paid for me already as they forget that he bought a cup of corn....
=.=
sweat...
if I were the boss...I think I will cry for hire this kind of worker....
haiz....
pity le...