We have 20% and 60% solutions and need 80 ml of 50%
A) x + y = 80
B) .20x + .60y = (80 * .5)
Multiplying A) by -.2
A) -.2x -.2y = -16 Then adding this to B) we get
.4y = 24
y = 60 ml of 60%
x = 20 ml fo 20%
Source: 1728.com/mixture.htm
Answer:
The cost of the dinner before other costs is $14.20
Step-by-step explanation:
To solve this, we write the following equation:
x + .11x + .20x = 18.60
This is because in addition to paying for the dinner (x), she also has to pay 11% of it and another 20% of it. Now we can combine like terms and solve.
1.31x = 18.60
x = 14.20
Answer:
(b) 5.
Step-by-step explanation:
The bottom numbers are calculated from the 2 above them according to the formula:
c = 15(a + b)
- because: 75 = 15(2 + 3) and
165 = 15(7 + 4)
Therefore if the unknown number is x :
285 = 15(14 + x)
285 = 210 + 15x
15x = 285 - 210
15x = 75
x = 5.
Answer:300/1200
Step-by-step explanation:part/whole = %/100
300/1200 =25
/100
