Answer:
16 cakes
Explanation:
A baker can bake 12 cakes every 45 minutes
45 minutes equals 3/4 hours
so every 1/4 hour (15 minutes), a baker can bake 12/3 = 4 cakes
if baker can bake 4 cakes every 1/4 hour, then number of cakes every hour is 4 x 4 = 16 cakes
1/4 hour (15 minutes) = 4 x 1/4 = 1 hour (60 minutes)