Hayden wanted to investigate whether there was a difference in the time spent in the checkout line between two grocery stores. She went to Safeway on a Tuesday morning and recorded the time, in minutes, it took 30 customers to go through a checkout line. Then she went to Whole Foods on Tuesday afternoon and recorded the time it took 30 customers to go through a checkout line. Hayden calculated the mean number of minutes for the customers in each line. She intends to conduct a two-sample t-test for a difference in means between the two stores. Have all conditions for inference been met

If the value of cos330°is√3/2 then find cos 165°.

Suppose we have a set of small wooden blocks showing the 26 letters of the english alphabet, one letter per block. (think of scrabble tiles.) our set includes 10 copies of each letter. we place them into a bag and draw out one block at a time. (a) if we line up the letters on a rack as we draw them, how different ways coukl we fill a rack of 5 letters? (b) now suppose we just toss our chosen blocks into a pile, and whenever we draw a letter we already have, we put it back in the bag and draw again. how many different piles of 5 blocks could result? possible? piles will contain at least one repeated letter? (c) if we draw out 5 blocks wit hout looking at them, how many different piles are (d) if we draw out 5 blocks without looking at them, how many of the possible 2. (4) consider the following formula. 12 give two different proofs, one using the factorial formulas and the other combina torial.

At the start of 2014 lucys house was worth ? 200 000. the value of the house increased by 5% every year. workout the value of her house at the start of 2017