90=6x+3x
90=9x
90/9=x
10=x
3x=3*10=30
6x=6*10=60
hope this helped
Answer:
The hypotheses used in this situation


Step-by-step explanation:
We are given that Business Week reported that at the top 50 business schools, students studied an average of 14.6 hours.
Mean = 
Claim : The amount UMSL students study is different from this 14.6 hour benchmark.
The hypotheses used in this situation


-2° was the initial temperature as it dropped to -5°
-2-5=-7
Hope this helped