15=-2(2t-1) -- expand brackets
15=-4t+2 -- subtract 2
13=-4t -- switch signs, best to have a positive variable
4t=-13
t=-13/4
Answer:
You can distribute the 5 into the parentheses, or u can divide on both sides to get rid of the 5. Either way, you're going to get the same answer.
Fu/ac=mu/bc so 27/36=mu/24 so mu= 18
answer
240 standard versions
set up equations
s = number of standard versions
h = number of high quality versions
the total size of all standard versions would be 2.3s since each standard version is 2.3 MB
the total size of all high quality versions would be 4.4h since each standard version is 4.4 MB
add them together to get the total size (2664 MB) of all versions
2664 = 2.3s + 4.4h
since the high quality version was downloaded twice as often as the standard, we can say that
h = 2s
substitute h into equation and solve
2664 = 2.3s + 4.4h
h = 2s
2664 = 2.3s + 4.4(2s)
2664 = 2.3s + 8.8s
2664 = 11.1s
s = 2664/11.1
s = 240
Hmm all of them have the chance to be chosen but u got to aim of what u want to get