Answer: 7
Step-by-step explanation:
3n=21
n=7
Answer: 4
Step-by-step explanation: To have an equation with no solution you have to get something like 0=1 meaning you have to remove all the variables. In this equation you would distribute to get xy+2y+2x=2x+12+4x where y is the missing number. then combining like terms you get xy+2x+2y=6x+12. Subtracting 2x from both sides you get xy+2y=4x+12. Now to get the variables gone y has to be 4 so that the variables to cancel out. By plugging in 4 you can see this works; 4x+8=4x+12 and by subtracting 4x from both sides you get 8=12 which is not true meaning there is no solution.
1. this is a series of squares Formula is an = n^2
2. Arithmetic series with common difference d = -2.
an = a1 + (n-1)d = 3 -2(n-1)
Cant see the rule for Number 3
Given:
Initial price of the stock=$43.85
Change for the first two days=+$2.70
Change for next two days=-$1.10
Last day=-$4.45
The objective is to find the price at the last day.
Let's take the price at final day as <em>x</em>.

Hence, the price of the stock at the last day is $42.6
Using it's concept, it is found that the probability of being a girl and choosing lemonade is given by:
b. 0.2.
<h3>What is a probability?</h3>
A probability is given by the <u>number of desired outcomes divided by the number of total outcomes</u>.
In this problem, out of 130 people, 26 are girls who choose lemonade, hence the probability is given by:
p = 26/130 = 0.2, which means that option b is correct.
More can be learned about probabilities at brainly.com/question/14398287
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