The cost of 11 pencil and 3 erasers is rupees 50 and the cost of 8 pencils and 3 erasers is rupees 38 Find the cost of pencils and erasers.

5 pencils and 7 pens together cost Rs.50 whereas 7 pencils and 5 pens together cost rs.46 Find the cost of one pencil and that of one pen.

The cost of 4 kg. onion ,3kg wheat and 2kg rice is rupes 60. The cost of 2 kg onion , 4kg wheat and 6kg rice is rupes 90. The cost of 6kg onion 2kg wheat and 3 kg rice is rupes 70. Find cost of each item per kg by matrix method.

The cost of painting the total surface area of a cone at 25 paise per cm^(2) is rupes 176 .Find the volume of the cone ,If its slant height is 25 cm.

A family of 3 people went out for dinner in a restaurant. The cost of two dosai, three idlies and two vadais is Rs 150. The cost of the two dosai, two idlies and four vadais is Rs 200. The cost of five dosai, four idlies and two vadais is Rs 250. The family has Rs 350 in hand and they ate 3 dosai and six idlies and six vadais. Will they be able to manage to pay the bill within the amount they had?