THe number on the bottom is called the Notation
The two ways to find the ratio of the length is to turn the inches into feet or the feet into inches
So the answer can be solved like this:
1/36ft to 1/4ft which is 9:1 (blueprint size to actual size)
or
1/3in to 3in which is also 9:1 (blueprint size to actual size)
You can read 100 pages in 5 hours.
40 pages in 2 hours. We need to get the unit rate. In this case, we need to get the number of pages read in 1 hour.
40 pages ÷ 2 hours = 20 pages per hour.
20 pages per hours * 5 hours = 100 pages.
She asked her friends, which does not represent a random sample.
She tried to show cause and effect without doing an experiment (which includes simple random sample, control group, treatment, etc).
So the answer is she did not use a random sample, and tried to show cause and effect with an observational study.
This is a typical work problem in algebra. The approach to this is using the equation: Rt = 1, where R is the rate per person working, t is the amount of time worked by an individual. All their rates must equal to 1. The solution is as follows:
12/x + 15/x = 1
Solving for x,
x = 27 hours
So, if they work together, they can finish the work in 27 hours.