Answer:
There were 210 downloads of the standard version.
Step-by-step explanation:
This question can be solved using a system of equations.
I am going to say that:
x is the number of downloads of the standard version.
y is the number of downloads of the high-quality version.
The size of the standard version is 2.6 megabytes (MB). The size of the high-quality version is 4.2 MB. The total size downloaded for the two versions was 4074 MB.
This means that:

Yesterday, the high-quality version was downloaded four times as often as the standard version.
This means that 
How many downloads of the standard version were there?
This is x.

Since 




There were 210 downloads of the standard version.
For question 9 - It is stating that AE is equal to 38. So the length of the entire line is 38. We then need to look at which figures are actually useful to us, which in this case is AC which is 10. Therefore the answer is as simple as 38-10, which gives us an answer of 28 for the other half of the line, notated as CE.
From the table, the experimental Probability of rolling a 1 = 28/200 = 7/50
So for 25 rolls we would expect 7 * 25 / 50 = 3.5
answer: 4 times
2.5y + 3x = 27
5x - 2.5y = 5
Align the variables to make solving this easier.
2.5y + 3x = 27
-2.5y + 5x = 5
You can see that the 2.5y and -2.5y cancel each other out. Then add the 3x and 5x, and 27 + 5.
3x = 27
5x = 5
8x = 32
Divide both sides by 8.
x = 4
Now input that x into one of the equations to get y.
2.5y + 3(4) = 27
2.5y + 12 = 27
2.5y = 15
y = 6
The answer to this system of equations is x = 4, y = 6. (4, 6)