All of them are true.
Refer to calculation for understanding.
121.5
121.5 rounded to nearest whole number is 122 --> 121.49 rounded to the nearest whole number is 121
Y=15x-200
y=15(10)(4)-200; you multiply by 4 because there are 4 weeks in a month.
y=150(4)-200
y=600-200
y=400; they would make a $400 profit.
2 cups of raisins = 1 trail mix
12 cups of raisnin= 6 trail mix
You would use the formula for the specific term you wish to find;
The formula is:

a = starting value of the sequence
d = the common difference (i.e. the difference between any two consecutive terms of the sequence)
n = the value corresponding to the position of the desired term in the sequence (i.e. 1 is the first term, 2 is the second, etc.)
Un = the actual vaue of the the term
For example, if we have the arithmetic sequence:
2, 6, 10, 14, ...
And let's say we want to find the 62nd term;
Then:
a = 2
d = 4
(i.e. 6 - 2 = 4, 10 - 6 = 4, 14 - 10 = 4;
You should always get the same number no matter which two terms you find the difference between so long as they are both
consecutive [next to each other], otherwise you are not dealing with an arithmetic sequence)
n = 62
And so: