Explanation:
let the number of mittens sold be m and scarves sold be s.
m + s = 250
m = 250 - s --(1)
10m + 20s = 3600 --(2)
sub (1) into (2):
10(250 - s) + 20s = 3600
2500 + 10s = 3600
s = 110
when s = 110, m = 140
Topic: Simultaneous equations
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