Answer:
7.5 L of 10% solution and 22.5 L of 30% solution
Step-by-step explanation:
Volume of 10% solution plus volume of 30% solution = total volume of 25% volume.
x + y = 30
Acid in 10% solution plus acid in 30% solution = total acid in 25% solution.
0.10 x + 0.30 y = 30 × 0.25
0.10 x + 0.30 y = 7.5
Solve the system of equations, using either substitution or elimination. I'll use substitution:
x = 30 − y
0.10 (30 − y) + 0.30 y = 7.5
3 − 0.10 y + 0.30 y = 7.5
0.20 y = 4.5
y = 22.5
x = 30 − y
x = 7.5
Sarah needs 7.5 L of 10% solution and 22.5 L of 30% solution.
8[2] + 6[2] = c[2]
64 + 36 = c[2]
100 = c[2]
c = 10
8 + 6 + 10 = 24 units
The answer is 0.81 repeating
Answer: 45
Step-by-step explanation:
Total number of 8th graders that signed up = 30
9 dropped out. So the total number 8th graders on board the game
= 30 - 9 = 21
46 2/3 % of the club are 8th graders i.e 21
Let T be the total number of students in the club
46 2/3 % T = 21
(140/3)% T = 21
(140/300)T = 21
T = (21x300)/140 = 45
Therefore, there are 45 students on the club
22. $31.25 divided by 25 = $1.25 for each ticket.
23. $1.50 times 5 = $7.50 to climb the rock wall.