how to know which is base currency in forex

niki_1079 (CA Practice ) (279 Points)

09 July 2008  

How we can derive which is base currency and which is quote currency in forex problem. As per ACI Convention base currency is written first and then quote currency like 

£/$ = 1.5 means

1£ = 1.5$

But in most of the questions base currency is written after quote currency like

Rs/$ = 45 means

1$ = 45 Rs.

How do we come to know in exam is there any method to know abt the base & Quote currency. If there is any then pls explain me.