So first, we need to take the important information given to us and ignore the useless ones:
-The plant is currently 3cm tall
-The plant grows 4cm a day
-How many days will it take to be 51cm?
So if you’re reading it correctly, you would do 51 minus 3 first. Why? Because we’re trying to find how many days it will take for the plant to be 51cm tall, not how many days it’ll take for the plant to grow 51cm. So 51-3=48. We have to find how many days it’ll take for the plant to grow 48cm.
Now we are given that the plant grows 4cm a day. Let’s set up an equation to help you understand this better, instead of just asking you to think.
48 = 4x
48 is the total cm the plant has to grow.
4 is the total cm the plant will grow a day.
x is the unknown variable. We will solve for x, which is the number of days it will take for the plant to reach the goal of 51cm.
If you remember basic Algebra, or Algebra I, this should be a piece of cake.
48 = 4x
Divide both sides by 4:
x = 12
So the answer is A. 12
It will take the plant 12 days to be 51cm tall.
Hope this helped!