A caterer's total cost for catering a party includes a fixed cost, which is the same for every party. In addition the caterer charges a certain amount for each guest. If it costs $300 to serve 25 guests and $420 to serve 40 guests, find the cost per guest. Write a system of equations for the situation and solve using inverse matrices.

The decibel level of sound is 50 db greater on a busy street than in a quiet room where the intensity of sound is watt/m2. the level of sound in the quiet room is db, and the intensity of sound in the busy street is watt/m2. use the formula , where is the sound level in decibels, i is the intensity of sound, and is the smallest sound intensity that can be heard by the human ear (roughly equal to watts/m2).

Asap the total attendance for all of a baseball league in 2012 was about 7.5×107 fans, while the attendance for the tornadoes in 2012 was about 1.5×106 fans. about how many times more was the attendance for the entire baseball league than the attendance for just the tornadoes? 50 times more 10 times more 2 times more 5 times more

Will used 20 colored tiles to make a design in art class. 5/20 of his tiles were red. what is an equivalent fraction for the red tiles?