Will has 24 t-shirts; 1/4 are yellow and 1/3 are white. how many t-shirts are not white neither yellow

For how answer my question this will be the last question can you answer in math subject

Arefrigeration system at your company uses temperature sensors fixed to read celsius (°c) values, but the system operators in your control room understand only the fahrenheit scale. you have been asked to make a fahrenheit (°f) label for the high temperature alarm, which is set to ring whenever the system temperature rises above –10°c. what fahrenheit value should you write on the label?

Factor and solve to find roots x squared -x - 90 =0