Number 5 is $25. Sorry, I couldn't do the rest.
Use the formula for an arithmetic sequence: 
= nth term
a = the first term in the sequence
n = term you are looking for
d = common difference between the terms
Answers
1. <em>I'm assuming you meant to type 0.2, 0.6, 1, 1.4...</em>
In that case, it is increasing by 0.4, so the next three would be:
0.2 + (4-1)(0.4) = 1.8...
=> 1.8, 2.2, 2.6.
2. Here it's reducing by 0.25, so start with:
4 + (5-1)(-0.25) = 3...
=> 3, 2.75, 2.5
Number 2 is not an equation.
Answer: 5 (x > 12) or 5 + m(12 - x) (x < 12)
Step-by-step explanation:
flat fee $5 for first x days +
m dolars per day after x days
So, if x > 12, for 12 days the fee is $5 because it is a flat fee that do not depend of the numbers of day.
But, we do not know how many days x is, so
if x < 12, a person will pay, for 12 days, the m times the difference of the days passed x:
5 + m(12-x)
Answer:
- 40 popcorns and 90 pretzels sold.
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Let the number of popcorns is x and pretzels is y.
Set up equations:
- x + y = 130
- 2.5x + 2y = 280
Solve by elimination, multiply the first equation by 2 and subtract from the second equation:
- 2.5x + 2y - 2x - 2y = 280 - 2*130
- 0.5x = 280 - 260
- 0.5x = 20
- x = 20/0.5
- x = 40
Find y:
- 40 + y = 130
- y = 130 - 40
- y = 90
