Question

arti bought 20/7 kg of peas from the market. she used 1/7 of this and stored the remaining for next day. how many kg of peas did she store for the next day 2

Answer 1

Amount of peas Aarti brought = 20/7 kg
As she used up 1/7 of the brought amount, the remaining amount is 6/7 of the brought amount.
So, the remaining amount for the next day = 6/7 of 20/7 kg
                                                                    = 6/7 * 20/7
                                                                    = 120 /  49 kg
∴The amount of peas remained for the next day = 120/49 kg

Hope my answer helps you..

Answer 2

we will subtract the amount of peas bought by amount of peas used 
i.e.
20/7-1/7=19/7
that means 19/7 will be the peas stored for the remaining next day.
if she uses 1/7 for each next day then for  next 2 days it will become 1/7+1/7=2/7
now,
sutract  the pras stored for the remaining next day by the amount of peas she uses for next 2days.
19/7-2/7=17/7 will be the answer 

i hope it will help you