Answer:
5400
Explanation:
To form an equation we need to replace the words by letters, let's just use x and y for this.
Let hour = y and bacteria = x
1 hour = 3 bacteria
So this can be written as:
(a) y = 3x
Now we're told that there are 150 bacteria.
Bacteria = 150 and, x will be as well.
(b) x = 150
y = 3x = 3(150) = 450
y = 3x = 3(150) = 450 12y = 450 × 12 = 5400
y = 3x = 3(150) = 450 12y = 450 × 12 = 540013 hours = 5400 bacteria