Answer:
b)
Step-by-step explanation:
Answer:
q=8
Step-by-step explanation:
To solve for q, we need to get q by itself. To do this, preform the opposite of what is being done to the equation. Also, everything must be done to both sides of the equation.
8q-15=49
Add 15 to both sides, since 15 is being subtracted.
8q-15+15=49+15
8q=64
Divide both sides by 8, since 8 and x are being multiplied.
8q/8=64/8
q=8
13.15 ounces of 72% acid and 71.85 ounces of 25% acid are needed
<u>Step-by-step explanation:</u>
Total mass of acid required= 85 ounces
Let the mass of 72% acid be 'a'
Let the mass of 25% acid be 'b'
a + b = 85
b = 85-a
85(40/100) = a(72/100) + b(25/100)
85(2/5) = a(72/100) +(85- a) (25/100)
34 = (72a/100) + (2125/100) - (25a/100)
34 - (2125/100) = (72a + 25a) /100
(3400-2125)/100 = 97a /100
97a = 1275
a = 13.15 ounces
b = 85 - 13.14
b = 71.85 ounces
13.15 ounces of 72% acid and 71.85 ounces of 25% acid are needed
You should pick none of the above
