Question

Totsakan enlarged the size of a photo to a

Answer 1

The width of the enlarged photo is 9 inches.

Given: 
Original length = 2 inches
Original width = 1 inch
Extended length = 18 inches
Extended width = ?

2:1 = 18:x
2x = 1*18
2x = 18
2x/2 = 18/2
x = 9   * extended width.

to check:
2:1 = 18:9
2*9 = 1*18
18 = 18