Answer:
S₁₅ = 645
Step-by-step explanation:
The sum to n terms of an arithmetic sequence is
= [ 2a₁ + (n - 1)d ]
where a₁ is the first term and d the common difference
Using the nth term formula = 5n + 3 , then
a₁ = 5(1) + 3 = 5 + 3 = 8
a₂ = 5(2) + 3 = 10 + 3 = 13 , then
d = a₂ - a₁ = 13 - 8 = 5
Thus
S₁₅ = [ (2 × 8) + (14 × 5) ]
= 7.5( 16 + 70)
= 7.5 × 86
= 645
8/2.79 = 1/2.867, or $2.86 per each oz
15/5.54 = 2.707/1, or 2 oz for every 1 dollar
the 15 oz jar of salsa has the better unit rate
hope this helps
Answer:
The concentration is simply 36%
Step-by-step explanation:
In this question, we are concerned with calculating the concentration of a new mixture formed from mixing some liters of each of two vinegar variants of different concentrations.
We proceed as follows;
The concentration of the new solution will contain 12% of 13L vinegar A and 70% of 9L vinegar B
13L of vinegar A will contain 13 * 12% = 13 * 0.12 = 1.56
9L of 70% vinegar B will contain 9 * 70% = 9 * 0.7 = 6.3
Now, the new mixture has a total volume of 13 + 9 = 22L
The concentration of the new mixture will thus be;
(1.56 + 6.3)/22
= 0.357 and that’s approximately 0.36 or simply 36%
For lines to be parallel, they have to have the same slopes. For the equation given as Ax + By + C = 0, the slope is -A / B. Equating the slopes of the given equations of lines,
- (3 / -5) = - (2 / k)
The value of k is equal to -10/3.