Answer:
Last month it sold 338 cakes.
Step-by-step explanation:
Let total cakes this month,last month and last 3 months be x,y and z respectively,
x = y + 10...
x = 3z
z = 116
Now, we have to find y,
x = y + 10
or, 3z = y + 10
or, 3•116 = y + 10
or, 348 = y + 10
or, y = 348 - 10
so, y = 338