The length of time a particular smartphone's battery lasts follows an exponential distribution with a mean of ten months. A sample of 64 of these smartphones is taken. Find the probability that the sample mean is between seven and 11.

Cass decided to sell game programs for the hockey game. the printing cost was over 20 cents per program with a selling price of 50 cents each. cass sold all but 50 of the programs, and made a profit of $65. how many programs were printed? letting p represent the number of programs printed, set up an equation that describes this situation. then solve your equation for p.

Determine the number of girls in a math class with 87 boys if there are 25 girls for every 75 boys

Kathy spent 5/8 of her money on books and another 1/6 of her money on stationeries. what fraction of kathy’s money was left?