Question

Under a project of 'one child one tree' undertaken by a school students plants
the trees in a pattern of first row three plants, second row 5 plants and 3 row
7 plants and so on. The last row has 37 plants. Find the number of students in
the school.​

Answer 1

plants in first row--------3

plants in second row--5

plants in third row------7

i.e., AP is 3,5,7.....37.

we have a=3

d=5-3=2

an=35

we have to find n.

an=a+(n-1)d

37=3+(n-1)*2

37-3=(n-1)*2

34/2=n-1

17+1=n

i.e. n=18...

Answer 2

I have attached the answer in the photo, hope all students can get the answer and can resolve the query