Given:
There are 19 oak trees in a park.
There will be 56 oak trees in the park the plantation.
To find:
How many oak trees did they plant today?
Solution:
We have,
Initial number of oak trees = 19
Number of trees after plantation = 56
Now, the number of oak trees they plant today is
New trees = Number of trees after plantation - Initial number of oak trees
= 56 - 19
= 37
Therefore, they did plant 37 oak trees today.