Answer:
B.
Mn = Mn-1 + 125 for n > 1 ; M1 = 3,875
Step-by-step explanation:
Since they tell us after 1970, the first data would be that of 1971 and also that if we started since 1970, we do not know the data of 1969, therefore answer B is correct.
Replacing:
Let M1 = 1971 then Mn-1, that is M0 = 1970, we know that the population of 1970 the population is 3750, because it would be 125 less than the subsequent year, and in 1975 there are 3875. Therefore:
in n = 1
M1 = M0 + 125
3875 = 3750 + 125
this gives an equality, thus fulfilling the equation.
Answer:
The correct answer is x = 3 and y = 2.
Step-by-step explanation:
There are many ways to solve systems of equations like this, but I'm going to use substitution. This means taking the value of y given by the second equation and plugging it into the first equation. This is modeled below:
2x - y = 4
2x - (-2x+8) = 4
Now, we can simplify the left side of the equation.
2x + 2x - 8 = 4
4x - 8 = 4
We should add 8 to both sides as the next step.
4x = 12
Now we can divide by 4.
x = 3
To solve for y, we can substitute this value found for x back into either one of our original equations.
y = -2x + 8
y = (-2*3) + 8
y = -6 + 8
y = 2
Therefore, the correct answer is x = 3 and y = 2.
Hope this helps!
Answer: 37 kilograms of walnuts should be mixed.
Step-by-step explanation:
Let x represent the number of kilograms of peanuts needed to make the mixture.
Let y represent the number of kilograms of walnut needed to make the mixture.
The mixture to be made is 100 kg. It means that
x + y = 100
The worth of the mixture is $3.24 per kilogram. It means that the total worth of the mixture is
3.24 × 100 = $324
peanuts cost $2.50 per kilogram and walnuts cost $4.50 per kilogram. It means that
2.5x + 4.5y = 324- - - - - - - - - -1
Substituting x = 100 - y into equation 1, it becomes
2.5(100 - y) + 4.5y = 324
250 - 2.5y + 4.5y = 324
- 2.5y + 4.5y = 324 - 250
2y = 74
y = 74/2 = 37
x = 100 - y = 100 - 37
x = 63
