The ratios 12:24, 15:30, and 18:36 form a pattern of equivalent ratios in the multiplication table below.

A multiplication table.

Which method can find other equivalent ratios for this pattern?
Multiply 3 and 6 by the same factor, and write the products as a ratio.
Multiply 2 and 8 by the same factor, and write the products as a ratio.
Multiply 4 and 6 by the same factor, and write the products as a ratio.
Multiply 1 and 8 by the same factor, and write the products as a ratio.