How long does it take to put 20 calligraphy works together into a rectangle 5 cm long and 4 cm wide?

Glue 20 calligraphy works with a side length of 2 decimeters together and attach lace around them, so that the lace needs at least 36 decimeters.

When 20 pieces of calligraphy are put together into a square, there is the least lace around it.

So it is a 4x5 rectangle.

The length is 5×2= 10 decimeter.

The width is 4×2=8 decimeters.

Lace at least =2×( 10+8)=36 decimeters.

Extended data:

Multiplication calculation, the product of several numbers is multiplied by a number, so that any factor in the product can be multiplied by this number and then multiplied by other numbers. For example: (25×3 × 9)×4=25×4×3×9=2700.

Multiply a number by the difference between two numbers. You can multiply this number by the minuend and the minuend respectively, and then subtract the product. For example: (137-125) × 8 =137× 8-125× 8 = 96.