Let us convert the percentages to decimal format first.. so 5% is just 5/100 or 0.05 and 15% is just 15/100 or 0.15
so hmmm, so, let's say it needs "x" amount and "y" amount of each respectively, so, whatever "x" and "y" are, they must add up to 100, and whatever their concentration is, must add up to what the mixture yields
thus

solve for "x"
what's "y"? well, y = 100 - x
Answer:
-1
Step-by-step explanation:
Answer:
(2, -7)
x = 2
y = -7
Step-by-step explanation:
Let's solve this system of equations by elimination.
Start by multiplying the first equation by 2:

Next, multiply the second equation by 3:

Notice that both equations now have a "6y", meaning we can subtract both equations and thereby eliminating the variable "y" from the equation:

Divide both sides by 23

Substitute 2 for "x" to solve for "y".

Subtract 8 from both sides:

Divide both sides by 3:

Therefore the answer is:

Additional Comments:
Note that we can only divide, subtract, multiply, or add both sides of the equation by the same quantity due to the Division, Subtraction, Multiplication, or Addition Property of Equality. These properties state that if you divide/subtract/multiply/add one side of the equation by one quantity, you must do the same to the other side of the equation so that it remains an equation.
Answer:
2 and 7/8
Step-by-step explanation:
3 + 3/8 - 1/2
3 + 3/8 - 4/8
3 - 1/8
2 and 7/8
If he has a measuring cup that holds 1/8 and not 1/4 he just has to dip it twice.