We can divide the above figure into two rectangles MNSR and OPQS.
The dimension of rectangle MNSR is 3 x 4 (Since, MR = 3 and MN = 4).
So, area of rectangle MNSR = 3* 4 = 12 square units.
Similarly dimension of rectangle OPQS is 3 x 1 because
PQ = MR - NO = 3 - 2 = 1
SQ = RQ - MN = 7 - 4 = 3.
So, area of OPQS = 3* 1 = 3 square units.
Hence, the area of polygon MNOPQR = Area of rectangle MNSR that is 12 square units + Area of rectangle OPQS that is 3 square units.
= 12 + 3
= 15 square units.
Hope this helps you!