Answer:
The correct option is;
(C) 28
Step-by-step explanation:
The information given are that;
The total number of students = 1000
The number of students in each row are consecutive positive numbers
Let the number of students in the first row be x,
Let the number of rows be 17
We have;
The number of students in the last row = x + 16
The number of students in the penultimate row = x + 15, we continue to get;
n×x + n/2×(n-1) = 1000
(The term n/2×(n-1) is from the sum of an arithmetic progression formula)
Which gives;
17×x + 17/2×16 = 1000
17×x = 1000 - 17/2×16 = 1000 - 136 = 864
x = 864/17 = Which is not an integer,
We continue checking till we get to 25 rows which gives;
25×x + 25/2×24 = 1000
25×x + 300 = 1000
25×x = 1000 - 300 = 700
x = 700/25 = 28
The number of student in the first row = 28 students.
