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lets x stands for non-Canadian stamps, so
the number of Canadian stamps is 3x
together Jane has x + 3x = 4x stamps..
so we have only to check if the numbers below are divided by 4 with no remainder
only 54 doen't divide by 4
n. 检查，支票，账单，制止，阻止物，检验标准，方格图案
