Answer:
- <em>0.75</em><em> liters of 5% hydrochloric acid solution </em>
- <em>0.25</em><em> liters of 45% hydrochloric acid solution.</em>
Step-by-step explanation:
Let us assume that, x liters of the 5% hydrochloric acid and y liters of the 45% hydrochloric acid solutions are combined.
As Rajan need total of 1 liter of solution, so
i.e 
--------------------1
As Rajan needs 5% hydrochloric acid and 45% hydrochloric acid to make a 1 liter batch of 15% hydrochloric acid, hence acid content of the mixture of two acids will be same as of the final one, so
i.e 
-------------2
Putting value of x from equation 1 in equation 2,
Putting the value of y in equation 1,
Therefore, Rajan must use 0.75 liters of 5% hydrochloric acid solution and 0.25 liters of 45% hydrochloric acid solution.
Answer:
Step-by-step explanation:
<u>This is an AP with:</u>
- The first term a₁ = 12
- Common difference d = 3
- Number of terms n = 40
<u>Number of the seats:</u>
- Sₙ = 1/2*n(a₁ + aₙ) = 1/2n(2a₁ + (n - 1)d)
- S₄₀ = 1/2*40(12*2 + 39*3) = 2820 seats
<u>Formula of nth term:</u>
- aₙ = a₁ + (n - 1)d
- aₙ = 12 + (n - 1)*3 = 12 + 3n - 3 = 3n + 9
- aₙ = 3n + 9
Lets say the number is x so we can make an equation
If is at least 21, that means it has to be greater then or equal to it.
6+5*x>=21
You can subtract 6 from both sides
5*x>=15
Then divide both sides by 5
x>=3
You can conclude that the number is greater then or equal to 3.
Round 31.9 up to 32 so you can divide it by 4 to get about 8.
If there aren't any specific requirements for the equation, here are a few choices:
2³ = 8
64 / 8 = 8
2x + 4 = y (where x = 2)
x² - 1 = y (where x = 3)
