30 = 80*t
t = 30/80 = 3/8 hr
3/8 hr * 60 min/hr = 180/8 = 22.5 min
Three ventilation fans, each working alone, can clear the smoke out of a room in 12 hours, 16 hours, and 24 hours respectively. How long would it...
Answer:
A) 2(9x - 2)
Step-by-step explanation:
The greatest common factor of 18x and -4 is 2.
B is wrong because 18 is not the greatest common factor of both, since 4 cannot be divided by 18 and result in a whole number.
C is wrong because 18x cannot be divided by 4 to produce a whole number.
D is wrong because it restates the problem in a different way, therefore not factoring it completely. 1 is a common factor of both, but not the greatest.
→ 
8 and 10 can both be divided by 2. So, 8 ÷ 2 is 4 and 10 ÷ 2 is 5.
Hope this helps :)

=

equals
k = 15.6
First, simplify

to 1.2. Your problem should look like:

= 1.2
Second, multiply both sides by 13. Your problem should look like: k = 15.6, which is the answer.