Okay, let's break this down.
We first need to multiply the number of rows now with the plants he will plant in each row. 3 x 3 = 9.
Now, we need to do some more multiplication. Since Randy wants to plant 4 times as many rows as this year, we need to multiply the number of rows this year, and the number of rows next year. 4 x 3 = 12.
Now, we can multiply the number of rows with the number of plants. 12 x 3 = 36.
You could have also multiplied the number of rows this year with the number of plants, 3 x 3 = 9. Then, you can multiply that with the number of rows Randy wants to plant next year. 9 x 4 = 36.
Happy learning!