Answer:
Get a calculator
Step-by-step explanation:
Most of the time for simple math like multiplying 2 digits, it is easiest if you just get a calculator. It saves a lot of time.
If you can't get a calculator then i recommend memorizing some common equations.
For example 10*15= 150
so that if you get 12*15=?, you can easily just add two extra 15's to your answer of 150.
15+15 is 30, and 30+150(from 10*15)=180.
Therefore 12*15=180.
:) Hope that helped!
The 9 is in the tenths place so it should be 9x1/10. Meaning it would be 100+3x1+9x1/10+3x1,000
Answers:
- a) Stratified random sampling, or simply stratified sampling. Each group individually is known as a stratum. The plural is strata. The key here is that each stratum is sampled, though we don't pick everyone from every stratum. We randomly select from each unit to have them represent their unit. Think of it like house of representative members that go to congress. We have members from every state, but Be sure not to mix this up with cluster sampling. Cluster sampling is where we break the population into groups or clusters, then we randomly select a few clusters in which every individual from those clusters is part of the sample.
- b) Simple random sampling (SRS). This is exactly what it sounds like. We're randomly generating numbers to help determine who gets selected. Think of it like a lottery. A computer is useful to make sure this process is quick, efficient and unbiased as possible. Though numbers in a box or a hat work just as well.
For each of the methods mentioned, they aren't biased since they have randomness built into their processes.
65 is the answer. Solve the first equation and then plug in.
Let's say the cost of student tickets is x and the cost of adult tickets is y. Then:
(1) 12y + 6x = 138
(2) 5y + 11x = 100
If we rearrange equation (1) we get:
12y = 138 - 6x
Now divide each side by 12:
y = 11.5 - 0.5x
We can now substitute this into equation (2):
5(11.5 - 0.5x) + 11x = 100
57.5 - 2.5x + 11x = 100
8.5x = 42.5
x = 5, therefor the cost of a student ticket is $5.00
