Marta has $50 to spend on sketches. She wants to display them in an array of 3 rows, with 4 sketches in each row. Marta wants to include each type of sketch at least two times in her array. How many sketches does Marta want?

6 different sketches each in 2 quantity is required.

Explanation:

Given:

Marta has $50

She wants to display 4 sketches in each row

Number of row is 3

Total number of sketches = 3 X 4

= 12

Since, Marta wants to include each type of sketch at least two times in her array, the number of sketches of each type would be 12/2 = 6

Therefore, 6 different sketches each in 2 quantity is required.