A piepie is divided into 2020 equal pieces. GlennGlenn and SophieSophie each ate one fourth 1 4 of the piepie on MondayMonday. The next day, SophieSophie ate one fifth 1 5 of the piepie that was leftover. How many of the pieces of the original piepie remain? Explain your reasoning. Together, GlennGlenn and SophieSophie ate one fourth 1 4 piece(s) on MondayMonday, and SophieSophie ate one fifth 1 5 piece(s) the next day. To find the number of pieces that remain, add these numbers to the total number of pieces. So, 0.450.45 pieces of the original piepie remain.

Pieces remaining =  1 - (1/4 + 1/4) - (1/2 x1/5) = 1/2 - (1/2 x1/5) = 1/2 - 1/10 = 4/10

Therefore, 4/10 x 20 = 8 pieces.

Step-by-step explanation:

Sophie ate 1/4 = 5 pieces

Glenn ate 1/4 = 5 pieces

Remaining pieces = 20 - 5 - 5 = 10 pieces

On Monday, Sophie ate = 1/5 x 10 = 2 pieces

Therefore, remaining pieces = 10 - 2 pieces = 8 pieces

Sophie and Glenn consumed half of the pie the first day.  This is equal to 10 pieces.  The remaining pieces will be 10.  If, on Monday, Sophie ate 1/5 of 10 pieces, representing 2 pieces, the number left over is 10 Minus 2, which equals 8 pieces.