If the number of bacteria in a colony doubles every 105 minutes and there is currently a population of 45 bacteria, what will be the population by 315 minutes from now?

Jack did 3/5 of all problems on his weekend homework before sunday. on sunday he solved 1/3 of what was left and the last 4 problems. how many problems were assigned for the weekend?

Identify the expression equivalent to 4(x + x + 7) − 2x + 8 − 4 by substituting x = 1 and x = 2.

Which image (a’ b’ c’ d’) of abcd cannot he produced using only reflections ?