Subdivide the 8x10 grid below along the grid lines into nonoverlapping rectangles (some may be squares). Each rectangle must contain exactly one number; each number indicates how many small cells are contained within the rectangle.

From Mensa Puzzle Calendar 2018 by Fraser Simpson, Workman Publishing, New York. Puzzle for June 26.

4887777777

488CCCC466

488CCCC466

488CCCC466

7777777488

FFFFF99988

FFFFF99988

FFFFF99988

logic:

Lower 8 must be the lower of two possible positions or else 9 makes a hole.

So, 9 must be 3x3.

This allows 15 to have 5 at the bottom.

So, 6 must go exactly atop rt 8.

So, upper 7 is horizontal.

Lower 7 is horizontal flush lft., else hole.

Rt 4 descends vertically from top 7.

Finishing the top left becomes obvious.

*Edited on ***July 4, 2018, 3:19 am**