Write and solve an equation to find the number.
a) Seven less than twice a number
equals 19.
b) Eight decreased by 3 times a number equals 2.

Colby and jaquan are growing bacteria in an experiment in a laboratory. colby starts with 50 bacteria in his culture and the number of bacteria doubles every 2 hours. jaquan starts with 80 of a different type of bacteria that doubles every 3 hours. let x equal number of days. colbys experiment follows the model: a.) y=50*2^x b.) y=50*2^8x c.) y=50*2^12x jaquans experiment follows the model: a.)80*2^x b.)80*2^8x c.)80*2^12x

Jordan got 27 out of 90 correct on his test . what fraction of the marks did her get correct

Arational number that is equivalent to -20/4?