Answer:
Step-by-step explanation:
A. 5 invitations
b. 15 invitations
Comment if you need me to explain it.
Answer:
It is stratified random sampling.
Step-by-step explanation:
Stratified random sampling is a method of sampling that involves the division of a population into smaller sub-groups known as <em>strata.</em>
The strata are formed based on members' shared attributes or characteristics, in this case their race.
Stratified random sampling is also called <em>proportional random sampling</em> or <em>quota random sampling</em>
We can use elimination for these set of systems.
First, we need to set up our variables.
Belts=b
Hats=h
Now, the situation is 6 belts and 8 hats for $140. The situation after is 9 belts and 6 hats for $132.
Let’s set up our system of equations.
6b+8h=140
9b+6h=132
We need to eliminate a variable. Since b has coefficients of 6 and 9, we can easily eliminate b by multiplying the top equation by 3 and the bottom by -2.
18b+24h=420
-18b-12h=-264
Now let’s add.
12h=156
Let’s divide to get h by itself.
156/12=13=h
So a hat costs $13. We need to put in 13 for one of the equations so we can find the cost of a belt.
9b+6(13)=132
9b+78=132
We need b by itself.
9b=54
54/9=6
Belts are $6
We can also use the first equation to check our answers.
6(6)+8(13)
36+104
140.
So, the price of a belt is $6 while the price of a hat is $13.
