Two pipes are used to fill a water storage tank. the first pipe can fill the tank in
4 hours, and the two pipes together can fill the tank in
2 hours less time than the second pipe alone. how
long would it take for the second pipe to fill the
tank?
can someone , my parents can’t either ☹️

Apsychology student wishes to investigate differences in political opinions between business majors and political science majors at her college. she randomly selects 100 students from the 260 business majors and 100 students from the 180 political science majors. does this sampling plan result in a simple random sample? why or why not? no, because each group of 200 students in the sample does not have the same chance of being selected. yes, because each group of 200 students in the sample has the same chance of being selected. no, because each individual student does not have an equal chance of being selected. yes, because each individual student has the same chance of being selected.

Helena lost her marbles. but then she found them and put them in 44 bags with mm marbles in each bag. she had 33 marbles left over that didn't fit in the bags.

Tell whether the two rates form a proportion