let's recall that to find the inverse of any expression, we start off by doing a quick switcheroo on the variables, and then solve for "y".
2/5 and 1/3 have a common denominator of 15. 6/15, 5/15, and 4/15 add up to 15/15. So the chances of rock are 4/15. 120 divided by 15 is 8. Six times eight equals fourty eight, five times eight equals forty, and four times eight equals thirty two. So there are 48 classical songs, 40 jazz songs, and 32 rock songs.
One really simple way to find an equivalent fraction is just to multiply the numerator and denominator.
For example, for the first answer, 
, I simply multiplied the numerator and denominator each by 2. This gives you an equivalent fraction.
You can then continue with this process using numbers such as 3, 4, 5, and 6 as your multiplication factor.
Answer – C. (Convenience sampling)
The sampling method that is generally considered the weakest is convenience sampling. This is because in convenience sampling, there is usually no inclusion criteria identified prior to the selection of subjects. Convenience sampling involves getting participants wherever you can conveniently find them. Typically, the first available participants (or any other primary data source, as the case may be) will be used for the research without any additional requirements.Other names by which convenience sampling is known are: Incidental Sampling, Chunk Sampling, and Accidental Sampling.
