A chemical company makes two brands of antifreeze the first brand is 55% pure anti-freeze in the second brain is 80% pure anti-freeze in order to obtain 50 gallons of a mixture that contains 70% pure anti-freeze how many gallons of each brand of antifreeze must be used

Helll ! 1,400 tons of wheat of two different varieties was delivered to the silo. when processing one variety, there was 2% of waste and 3% during the processing of the second variety of wheat. after the processing, the amount of remaining wheat was 1,364 tons. how many tons of each variety of wheat was delivered to the silo?