A villager went to a hotel in a town with his big family. They consumed 23 idlies, 18 pooris, 7 dosas and 19 vadas. The bill come to Rs. 108. On next day, they consumed 34 idlies, 8 vadas, 22 pooris and 7 dosas. The bill came to Rs. 114. If an idli costs the same as a vada, what is the cost of one poori?
let the cost of vada and idli be x and dosa be z and poori be y
then , 42x +18y +7z = 108
42x +22y +7z = 114
now by elimination method , we get,
-4y = -6
y = 3/2 = 1.5
the cost of one poori is 1.5 rs.