Question

If 15 days are required to plough 10 bighas of land, then how many days will be required to plough 20 bighas of land ?​

Answer 1

30 days

because 10 x 2 = 20

therefore  15 x 2 = 30                                                                                                                          

Answer 2

time period to make a 10 bighas = 15

" " " " " " " " " =20

10:15 ::20:x

x=30