there is a certain number. If you add 30 7 to it, then subtract 22 7 from the previous result, and then subtract that difference from 59/7, after that you will get 19 7. What is a certain number?

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?

Which geometric principle is used to justify the construction below?

The table shown below gives the approximate enrollment at the university of michigan every fifty years. how many more students were enrolled at the university of michigan in 1950 than in 1900?