One week the music store sold 2 trumpets, 3 clarinets, and 5 violins for $1,240. The next week, they sold 3 trumpets, 1 clarinet, and 4 violins for $1,027. The following week, they sold 5 trumpets, 7 clarinets, and 2 violins for $2,091. Find the cost of a trumpet, clarinet, and violin. Answers:
Trumpet:
Clarinet:
Violin:

Write the product as a trinomial. (x + 2)(x + 3) x2 + 5x + 6 x2 + 6x + 6 x2 + 6x + 5 x2 + 5

An automated water dispenser fills packets with one liter of water on average, with a standard deviation of 5 milliliter. the manual says that after a year of operation the dispenser should be tested to see if it needs recalibration. a year later a number of filled packets are set aside and measured separately. it is found that the average packet now contains about 0.995 liters. does the dispenser need calibration? explain your answer.

Adrawer contains 12 identical white socks, 18 identical black socks and 14 identical brown socks. what is the least number of socks you must choose, without looking, to be certain that you have chosen two socks of the same colour?