Answer:
Step-by-step explanation:
If J can paint a room in 3 hours, in 1 hour she gets 
of the job done.
If A can paint a room in 4 hours, in 1 hour she gets 
of the job done. We need to find out how long it takes them if they paint together. The equation for this is:
where x is the number of hours it takes them to get the job done together. Multiply everything through by 12x to get
4x + 3x = 12 so
7x = 12 and
x = 1.7 hours to get the room painted together.
Answer:
x+1
Step-by-step explanation:
We know that x^2 -6x-7 is the product of two binomials.
We can solve this two ways, but the easier way is to simply factor rather than divide the area by width.
Two numbers, one of which being -7 allows for the sum of -6 and the product of -7.
Using this information, we can identify the other number is 1, so the length is x+1.
c. 4.6
21 X .22= 4.6
Calculating the variance requires finding the product of 21 and 22%. To make this easier we convert 22% into it's decimal form and construct the equation. To back check this answer we can use 10% of 21 voters which equals 2.1% then double that amount to reach 4.2%, knowing that we now have a close approximation of the variance we can eliminate answers a, b, and d, leaving c as the only logical choice.
