13 scarves in 6 days is 13/6=2⅙ which is more than 2 a day.
So at the rate of 2 a day, only 6*2=12 scarves would be knitted.
That means that there’s one scarf short. If the time can’t be extended, then it means that after knitting 2 scarves on the first day, 11 scarves have to be completed in the remaining 5 days. That means 11/5=2⅕ scarves. So he must complete 2 scarves in the second day and partly knit another the same day. The table below shows the daily progress by working faster:
DAY |
NUMBER OF SCARVES COMPLETED |
LEFT TO COMPLETE |
1 |
2 |
11 |
2 |
2+⅕=2⅕ (complete 2 and start another) |
8⅘ |
3 |
⅘+1+⅖=2⅕ (finish 1, do another, start the next) |
6⅗ |
4 |
⅗+1+⅗=2⅕ (finish 1, do another, start the next) |
4⅖ |
5 |
⅖+1+⅘=2⅕ (finish 1, do another, start the next) |
2⅕ |
6 |
⅕+2=2⅕ (finish 1, do 2) |
0 |