To divide a line segment AB in the ratio m : n (m, n are positive integers), firstly draw a ray AX such that ∠BAX is an acute angle. Now, along AX mark off m + n points at equal distances.
Suppose these m + n points marked on ray AX be A1, A2, A3, ..., Am, Am + 1, ..., Am + n. Then, join B to Am + n.
Here, m = 4 and n = 7
∴ m + n = 4 + 7 = 11
So, B is joined to the point A11.
Thus, in order to divide a line segment AB in the ratio 4 : 7, a ray AX is drawn first such that ∠BAX is an acute angle and then points A1, A2, A3, ... are located at equal distances on the ray AX and the point B is joined to A11.
Hence, the correct answer is option (b).