Some pupils in two different classes take a test. There are 18 pupils in 7X1 and 26 pupils in 7Y1. The mean mark for the pupils in 7X1 is 23. The mean mark for pupils in 7Y1 is 17.
Calculate the mean mark for the two classes combined.
Give your answer correct to 1 decimal place.

The function a represents the cost of manufacturing product a, in hundreds of dollars, and the function b represents the cost of manufacturing product b, in hundreds of dollars. a(t) = 5t + 2 b(t) = 7t - 2t +4 find the expression that describes the total cost of manufacturing both products, a(t) + b(t). a. 7t^2 - 7t + 2 b. 7t^2 + 3 +6 c. 7t^2 + 7t - 6 d. 7t^2 - 3t + 6

14. (05.02 lc) what is the value of y in the solution to the following system of equations? (5 points) 2x + y = −4 5x + 3y = −6

Determine if the outside temperature is a function of the time of day or if the time of day is a function of temperature and explain why or why not.