Answer: 75 students.
Step-by-step explanation:
In the data set we have a total of 10 + 8 + 7 + 5 = 30 students.
of those, 10 want to go to the park, the percentage is:
(10/30)*100% = 33.3%
Then, out of the 225, we can expect that a 33.3% (or 0.333 in decimal form) want to go to the park, this is:
N = 225*0.333% = 74.925
We can roud it up, and get N = 75
So Sally can expect that 75 students want to go to the park
Answer:
Cost of five blouses = $145
Step-by-step explanation:
Let
x = cost of blouse
y = cost of skirt
15x + 2y = 505 (1)
5x + 2y = 215 (2)
Subtract (2) from (1) to eliminate y
15x - 5x = 505 - 215
10x = 290
x = 290/10
x = 29
Substitute x = 29 into (2)
5x + 2y = 215 (2)
5(29) + 2y = 215
145 + 2y = 215
2y = 215 - 145
2y = 70
y = 70/2
y = 35
x = cost of blouse = $29
y = cost of skirt = $35
How much do 5 such blouses cost?
cost of a blouse = $29
Cost of five blouses = $29 × 5
= $145
Cost of five blouses = $145
4y+x= -1
-x -x
—————
4y=-x-1
— ——
4 4
=======
Y= -1/4x - 1/4
Hoped this helps
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.
