Out of the 50 students in Mrs. Green's class, 20 have a pet. What percent of the students in Mrs. Green's class have a pet?

The water has been on the stove y=9.5x+62.1 after how many minutes will the tempature be 138.1 f

When i add money am i supposed to make it like this 7+12 or 7.00+12.00 because i got 19 dollars for my answer

Lance lived in portugal and brazil for a total of 14 months to learn portuguese. he learned an average of 130 new words per month when he lived in portugal, and an average of 150 new words per month when he lived in brazil. in total he learned 1920 new words. write a system of equations to represent the situation. use x to represent portugal, and y to represent brazil