Question

.
(11) In a flower bed there are 23 rose plants in the first
ROW, 21 in the second, 19 in the third, and so on.
There are 3 rose plants in the last row. How many
rows are there in the flower bed?
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Answer 1

Answer:

11 rows

Step-by-step explanation:

according to arithmetic progression :

a=23

a2=21

a3=19

d=-2 (a2-a1) (21-23=-2)

an=3

by applying, an=a+(n-1)d

3=23+(n-1)-2

3-23= (n-1)-2

-20= (n-1)-2

-20/-2=n-1

10 =n-1

10+1=n

11=n ans.