Thread: Fruit trees

The fruit plants in my garden do not bear fruit during their first summer. The fruits are picked for
the next two years and then the plants become too woody and need to be pulled up. Occasionally
some of them die over winter. The last five years I had fruit on the following number of plants:
0, 11, 20, 27, 19
Assuming no plants die this winter, what is the fewest that I could have next summer?
A 0
B 1
C 7
D 8
E 19

i dont quite understand why the answer is A. pls explain. thank you


EDITS: thank you so much for the explanation!! i keep getting 1 cos i missed out the line where the tree may die in winter.

How about the following scenario. Remember that plants that don't die get pulled up after they have given fruit for two years.

Before summer 1: Plant 11 fruit plants.
Summer 1: 0 plants bear fruit.

Before summer 2: Plant 9 fruit plants.
Summer 2: 11 plants bear fruit.

Before summer 3: Plant 19 fruit plants.
Summer 3: 20 plants bear fruit.

Winther: 1 of the 9 plants planted before summer 2 dies.

Before summer 4: Plant no fruit plants.
Summer 4: 27 plants bear fruit.

Before summer 5: Plant no fruit plants.
Summer 5: 19 plants bear fruit.

Before summer 6: Plant no plants (but really not important, since plants planted this summer bear no fruit until next summer).
Summer 6: 0 plants bear fruit.

(Bracketed is the new plants for each year)

Code:

YEAR:      1         2          3          4          5           6

      (11) 0        11         11          0          0           0
                 (9)            9 (1 died) 8          0           0
                            (19)          19         19           0 
                                       (0)            0           0
                                                  (0)             0
         ===       ===        ===        ===        ===         ===
           0        11         20         27         19           0

Clear nuff?

i can not understand

Regards
garden maintenance tips

You typoed your name: should be Alex Robot !